Using 32-bit license on 64-bit install?



Depends on the program, but in general you should be fine.

If the vendor offers a 64-bit version of their program, but with a separate license (and you don't want to pay again), you can just install the 32-bit binaries of the program (with your existing license) and Windows x64 will be happy to run them.
 
If you are currently running a 32-bit version of Windows, you can only perform an upgrade to another 32-bit version of Windows. Similarly, if you are running a 64-bit version of Windows, you can only perform an upgrade to another 64-bit version of Windows.

To install a 64-bit version of Windows on a computer running a 32-bit version of Windows, you'll need to start, or boot, your computer using a 64-bit Windows installation disc.

If you start your computer using a 64-bit Windows installation disc, but your computer isn't capable of running a 64-bit version of Windows, you'll see a Windows Boot Manager error. You'll need to use a 32-bit Windows installation disc instead.

http://windows.microsoft.com/en-US/windows-vista/32-bit-and-64-bit-Windows-frequently-asked-questions
 
Generally, the problem would be if you tried to run a 64-bit program on a 32-bit pc, the contrary is now possible as Win 7 have a program folder x64 and another one x32 , so to solve any compatibility issues .