In IA 7.0 I found a requirement selection for a 64-bit OS but not a test feature.
The 'Get OS' method doesn't indicate if the OS (e.g. Vista) is 32-bit or 64-bit.
The 'Get System Settings' method returns the processor architecture but not the OS type.
I need to build a single setup for 32 and 64 bit systems that installs a few files differently on 64-bit systems.
I think the tick box effects how paths are detected as well. So you may want to have 2 installers but auto run the 64bit version when you detect 64bit mode in the 32 bit installer