so i think, the problem is around the launcher indeed,
That's technically rather difficult, since the launcher is just a fancy way to assemble a commandline - it can't do anything genuinely different.
I tried to start fgfs without any launcher and expected to be on a c172p mod. 81 in San Francisco, but got a 172p Mod 82 in Honolulu.
That's a very odd expectation since the default airport hasn't been San Francisco for ages.
All this sounds like you have some sort of version mixup still (aka somehow you have the launcher pointing at another aircraft variant than the commandline does).