Your terminology is not clear. What do you mean by downloading? Download in the AB PLC world means transferring the program from a PLC to your PC running the Logix programming software.
As well as in VMware under Windows 7 32-bit, I have it installed and working natively in both Windows 7 32-bit and 64-bit. How say you now?
It's always important to remember that each of our workstation's configurations are different in many, many ways and that one glove does not fit all.
While I believe it is most likely that Microsoft .NET Framework 1.1 is struggling to install under a 64-bit OS here, it could still be a 32-bit OS issue. In hindsight our good friend has actually not said which, yet.