Virtualization

I am not sure whether the admin studio repackager monitors 64 bit environment. But i say always do package on the lower version operating system and test it on higher version. This was the old scenario. But you can package it on 32 bit and try to test it on 64 bit. As the MSI has enough access in re-directing the folders to respective locations on a 64 bit machine.

Also you can create a complete x64 bit MSI which tells the MSI to install the application to 64 bit locations only. This option you can see in the release. Template summary property will diplay the x64.

On 64-bit operating systems, the Repackager automatically runs its x64 version. 

If you wish to override this default behavior and force the use of the 32-bit Repackager on 64-bit systems, use /ForceX86 command line switch for Repackager.exe