MultiUser.nsh and $PROGRAMFILES64
Shouldn't the macro MULTIUSER_INSTALLMODE_ALLUSERS in MultiUser.nsh use $PROGRAMFILES64 instead of $PROGRAMFILES (since $PROGRAMFILES64 reverts to $PROGRAMFILES on 32 bit). Or is there another way to use MULTIUSER_INSTALLMODE_INSTDIR to get it to point to "Program Files" instead of "Program Files (x86)" on a 64-bit OS?
32 bit apps go in the 32 bit (x86) program files, does not matter what the host OS is. If the thing you are installing is a 64 bit app, then yes, it should go in $PROGRAMFILES64
Well 32 bit apps is installed in "program files" at least on 32 bit XP. But I see what you mean, that there are times when $PROGRAMFILES64 isn't correct. Like installing a 32 bit app on a 64 bit OS.
So the best solution would be to use a define like MULTIUSER_INSTALLMODE_64 that is used in MULTIUSER_INSTALLMODE_ALLUSERS.