Hi Pete,
FlightSim Commander 8.2.1 runs fine communication with FSUIPC4.20
FSUIPC4.LOG file in the FSX Modules folder shows no errors:
********* FSUIPC4, Version 4.20 by Pete Dowson *********
User Name=""
User Addr=""
FSUIPC4 not user registered
WIDEFS7 not user registered, or expired
Running inside FSX on Windows Vista (SimConnect Acc/SP2 Oct07)
Module base=61000000
DebugStatus=0
530 System time = 19:46:10
..
1841 LogOptions=00000001
1841 SimConnect_Open succeeded: waiting to check version okay
7472 Running in "Microsoft Flight Simulator X", Version: 10.0.61637.0 (SimConnect: 10.0.61259.0)
7472 Initialising SimConnect data requests now
7472 FSUIPC Menu entry added
..
Sjaak