I am afraid that the only supported operating systems are as follows:
Microsoft® Windows® 7 (32-bit and 64-bit)
Microsoft® Windows® Vista® (32-bit and 64-bit)
Microsoft® Windows® XP (32-bit)
Also, there is nothing that could happen if you use the software in Windows 8 64-bit version. Most likely, the software will not work. But since it does support Windows 7 64-bit, there is a big possibility that the app will work flawlessly in Windows 8. Give it a try to see what happens.