Maybe someone can confirm, for some models, e.g. c172p, Lancair235 with HDR the Comm and NAV red display digits are fixed at 0000; with the c310dpm-3d or with HDR disabled the digits show frequencies properly. I've a suspiciion the KAP140 malfunctions , too, when HDR is enabled.
Edit I'm guessing (tm) it's to do with the non-working instruments use png while the ones that work seem to use rgb visuals.