Found it Gerd.
Actually I didn't notice first hand that your 4.10 package contained a whole com/maddox/il2/objects/air.ini and gui/game/buttons structure. After deleting those two folders from the pack (and the empty FlightModels folder), the mod works fine in 4.10.1 for me.
The buttons were already fine for me and according to the logfile they contain an F8F-2 FM already.
Thanks and best regards - Mike