Just to check all was copied well, here is the text from my new b1900d-autopilot.xml created following your instructions. Unfortunately there does not seem to be any way to attach a file here.
<?xml version="1.0"?>
<!--FGC-65 -->
<PropertyList>
<filter> <!-- Heading bug offset -->
<name>heading bug</name>
<debug>false</debug>
<type>gain</type>
<input>
<property>instrumentation/fgc-65/settings/hdg</property>
<offset>
<property>orientation/heading-magnetic-deg</property>
<scale>-1.0</scale>
</offset>
</input>
<output>instrumentation/fgc-65/internal/offsets/hdg-bug</output>
<period>
<min>-180</min>
<max>180</max>
</period>
<gain>1.0</gain>
</filter>
<filter> <!-- NAV1 heading offset -->
<name>NAV1 heading </name>
<debug>false</debug>
<type>gain</type>
<input>
<property>instrumentation/nav[0]/heading-deg</property>
<offset>
<property>orientation/heading-deg</property>
<scale>-1.0</scale>
</offset>
</input>
<output>instrumentation/fgc-65/internal/offsets/nav1-brg</output>
<period>
<min>-180</min>
<max>180</max>
</period>
<gain>1.0</gain>
</filter>
<filter> <!-- NAV2 heading offset -->
<name>NAV2 heading </name>
<debug>false</debug>
<type>gain</type>
<input>
<property>instrumentation/nav[1]/heading-deg</property>
<offset>
<property>orientation/heading-deg</property>
<scale>-1.0</scale>
</offset>
</input>
<output>instrumentation/fgc-65/internal/offsets/nav2-brg</output>
<period>
<min>-180</min>
<max>180</max>
</period>
<gain>1.0</gain>
</filter>
<filter> <!-- CRS1 heading offset -->
<name>CRS1 heading </name>
<debug>false</debug>
<type>gain</type>
<input>
<property>instrumentation/nav[0]/radials/selected-deg</property>
<offset>
<property>orientation/heading-magnetic-deg</property>
<scale>-1.0</scale>
</offset>
</input>
<output>instrumentation/fgc-65/internal/offsets/crs1-brg</output>
<period>
<min>-180</min>
<max>180</max>
</period>
<gain>1.0</gain>
</filter>
<filter> <!-- CRS2 heading offset -->
<name>crs2 heading </name>
<debug>false</debug>
<type>gain</type>
<input>
<property>instrumentation/nav[1]/radials/selected-deg</property>
<offset>
<property>orientation/heading-magnetic-deg</property>
<scale>-1.0</scale>
</offset>
</input>
<output>instrumentation/fgc-65/internal/offsets/crs2-brg</output>
<period>
<min>-180</min>
<max>180</max>
</period>
<gain>1.0</gain>
</filter>
<!--
Lateral Controllers
-->
<pi-simple-controller> <!-- Heading hold -->
<name>Heading Hold</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/lateral</property>
<value>HDG</value>
</equals>
</condition>
</enable>
<input>
<property>instrumentation/fgc-65/internal/offsets/hdg-bug</property>
</input>
<reference>
<value>0.0</value>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/roll</property>
</output>
<config>
<Kp>-1.0</Kp>
<Ki>0.0</Ki>
<min>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>-25.0</scale>
</min>
<max>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>25.0</scale>
</max>
</config>
</pi-simple-controller>
<pi-simple-controller> <!-- NAV1 hold -->
<name>Nav1 Hold</name>
<debug>false</debug>
<enable>
<condition>
<property>instrumentation/fgc-65/internal/nav-active</property>
</condition>
</enable>
<input>
<property>instrumentation/fgc-65/internal/offsets/crs1-brg</property>
<offset>
<property>instrumentation/nav/heading-needle-deflection-norm</property>
<scale>45.0</scale>
</offset>
</input>
<reference>
<value>0</value>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/roll</property>
</output>
<config>
<Kp>-1.0</Kp>
<Ki>0</Ki>
<min>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>-25.0</scale>
</min>
<max>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>25.0</scale>
</max>
</config>
</pi-simple-controller>
<pi-simple-controller> <!-- ILS hold -->
<name>ILS Hold</name>
<debug>false</debug>
<enable>
<property>instrumentation/fgc-65/internal/appr-active</property>
</enable>
<input>
<property>instrumentation/fgc-65/internal/offsets/crs1-brg</property>
<offset>
<property>instrumentation/nav/heading-needle-deflection-norm</property>
<scale>30.0</scale>
</offset>
</input>
<reference>
<value>0</value>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/roll</property>
</output>
<config>
<Kp>-1.0</Kp>
<Ki>0</Ki>
<min>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>-15.0</scale>
</min>
<max>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>15.0</scale>
</max>
</config>
</pi-simple-controller>
<pi-simple-controller> <!-- Roll -->
<name>Roll</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/lateral</property>
<value>ROLL</value>
</equals>
</condition>
</enable>
<input>
<property>/orientation/roll-deg</property>
</input>
<reference>
<property>instrumentation/fgc-65/settings/roll</property>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/roll</property>
</output>
<config>
<Kp>1.0</Kp>
<Ki>0.35</Ki>
<min>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>-30.0</scale>
</min>
<max>
<property>instrumentation/fgc-65/app-65a/BANK</property>
<scale>30.0</scale>
</max>
</config>
</pi-simple-controller>
<pid-controller> <!-- Aileron Controller -->
<name>Aileron Control</name>
<debug>false</debug>
<input>
<property>orientation/roll-deg</property>
</input>
<reference>
<property>instrumentation/fgc-65/internal/fd/roll</property>
</reference>
<output>
<property>controls/flight/aileron-filter</property>
</output>
<config>
<Kp>0.01</Kp>
<beta>1.0</beta>
<alpha>0.1</alpha>
<gamma>0.0</gamma>
<Ti>25.0</Ti>
<Td>0.01</Td>
<min>
<value>-1.0</value>
</min>
<max>
<value>1.0</value>
</max>
</config>
</pid-controller>
<filter> <!-- Aileron output filter -->
<name>aileron filter</name>
<debug>false</debug>
<feedback-if-disabled>false</feedback-if-disabled>
<initialize-to>output</initialize-to>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/app-65a/AP</property>
<value>AP</value>
</equals>
</condition>
</enable>
<input>
<property>controls/flight/aileron-filter</property>
</input>
<output>controls/flight/aileron-trim</output>
<type>noise-spike</type>
<max-rate-of-change>0.3</max-rate-of-change>
<min>-1</min>
<max>1</max>
</filter>
<!--
Pitch Controllers
-->
<filter> <!-- V/S Sample for ALT Hold/Track V/S to make smooth transitions -->
<name>V/S Sample</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>PITCH</value>
</equals>
</condition>
</enable>
<type>gain</type>
<gain>1.0</gain>
<input>autopilot/internal/vert-speed-fpm</input>
<output>instrumentation/fgc-65/settings/vs</output>
</filter>
<filter> <!-- Altitude hold -->
<name>Altitude hold</name>
<debug>false</debug>
<enable>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>ALT</value>
</enable>
<type>gain</type>
<input>
<property>instrumentation/altimeter/indicated-altitude-ft</property>
</input>
<reference>
<property>instrumentation/fgc-65/settings/alt</property>
</reference>
<gain>-1.0</gain>
<output>
<property>instrumentation/fgc-65/settings/vs</property>
</output>
<min>-1500</min>
<max>2000</max>
</filter>
<pid-controller>
<name>Glideslope hold</name>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>GS</value>
</equals>
</condition>
</enable>
<input>
<property>/instrumentation/nav[0]/gs-needle-deflection</property>
</input>
<reference>0</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/pitch</property>
</output>
<config>
<Kp>-5</Kp>
<Ti>10</Ti>
<Td>0.001</Td>
<u_min>-10</u_min>
<u_max>15</u_max>
</config>
</pid-controller>
<pid-controller> <!-- IAS hold -->
<name>IAS</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>IAS</value>
</equals>
</condition>
</enable>
<input>
<property>instrumentation/airspeed-indicator/indicated-speed-kt</property>
</input>
<reference>
<property>instrumentation/fgc-65/settings/ias</property>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/pitch</property>
</output>
<config>
<Kp>-1.0</Kp>
<beta>1.0</beta>
<alpha>0.1</alpha>
<gamma>0.0</gamma>
<Ti>10.0</Ti>
<Td>0.0</Td>
<min>-1</min>
<max>1</max>
</config>
</pid-controller>
<pid-controller> <!-- Vertical speed hold -->
<name>Vertical speed hold</name>
<debug>false</debug>
<enable>
<condition>
<or>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>VS</value>
</equals>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>ALT</value>
</equals>
</or>
</condition>
</enable>
<input>
<property>autopilot/internal/vert-speed-fpm</property>
</input>
<reference>
<property>instrumentation/fgc-65/settings/vs</property>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/pitch</property>
</output>
<config>
<Kp>0.0005</Kp>
<beta>1.0</beta>
<alpha>0.1</alpha>
<gamma>0.0</gamma>
<Ti>1.0</Ti>
<Td>0.00001</Td>
<min>-10</min>
<max>20</max>
</config>
</pid-controller>
<filter> <!-- Pitch tracking for smooth transitions -->
<name>Pitch tracking</name>
<debug>false</debug>
<enable>
<condition>
<not-equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>PITCH</value>
</not-equals>
</condition>
</enable>
<type>gain</type>
<gain>1.0</gain>
<input>orientation/pitch-deg</input>
<output>instrumentation/fgc-65/settings/pitch</output>
</filter>
<pi-simple-controller> <!-- Pitch -->
<name>Pitch</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/internal/vertical</property>
<value>PITCH</value>
</equals>
</condition>
</enable>
<input>
<property>orientation/pitch-deg</property>
</input>
<reference>
<property>instrumentation/fgc-65/settings/pitch</property>
</reference>
<output>
<property>instrumentation/fgc-65/internal/fd/pitch</property>
</output>
<config>
<Kp>1.0</Kp>
<Ki>0.0</Ki>
<u_min>-15</u_min>
<u_max>30</u_max>
</config>
</pi-simple-controller>
<pid-controller> <!-- Elevator trim controller -->
<name>Elevator Trim Control</name>
<debug>false</debug>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/app-65a/AP</property>
<value>AP</value>
</equals>
</condition>
</enable>
<input>
<property>orientation/pitch-deg</property>
</input>
<reference>
<property>instrumentation/fgc-65/internal/fd/pitch</property>
</reference>
<output>
<property>controls/flight/elevator-filter</property>
</output>
<config>
<Kp>-0.05</Kp>
<beta>1.0</beta>
<alpha>0.1</alpha>
<gamma>0.0</gamma>
<Ti>10.0</Ti>
<Td>0.0001</Td>
<u_min>-1</u_min>
<u_max>1</u_max>
</config>
</pid-controller>
<filter> <!-- Elevator filter -->
<name>Elevator filter</name>
<debug>false</debug>
<feedback-if-disabled>false</feedback-if-disabled>
<initialize-to>output</initialize-to>
<enable>
<condition>
<equals>
<property>instrumentation/fgc-65/app-65a/AP</property>
<value>AP</value>
</equals>
</condition>
</enable>
<input>
<property>controls/flight/elevator-filter</property>
</input>
<output>controls/flight/elevator-trim</output>
<type>noise-spike</type>
<max-rate-of-change>0.3</max-rate-of-change>
<min>-1</min>
<max>1</max>
</filter>
</PropertyList>