I’ve finally, for sure this time, fixed the 64-bit installation issue. I confirmed that I tested 1.3.119 on a 64-bit machine, but perhaps there was an uninstall that didn’t remove all the necessary Registry entries, so I didn’t detect that the 1.3.119 installer didn’t create everything. I’m not sure. Anyway, I tested 1.5.122 on a clean Registry (64-bit) and it works. I apologize for any issues you’ve had.
Please let me know if there’s still an issue on your machine. If nothing else, I can give you a Registry file to import that will fix it.