This involves language switching but also %PATH%, %PURPLEHOME% and all the other env. vars! (I'm actually surprised it's even running !)
The (Unicode NSIS) System::call's don't seem to deal with:
System::Call 'Kernel32::SetEnvironmentVariableA(t, t)***********'
If I remove the A's, and re-compile language switching works again, and all the other env.vars are set properly again !
(OS Windows XP sp 3)