The latest update of FL Studio (FL20.9.1.2826-Win10-64 build) runs well in a Windows 10 64-bit Bottle. Once again I have not been able to test many of the newer features, yet.
The previous FL edition had a problem on many systems where the new 2-step registration unlock procedure would need to be repeated every time the program was launched, but that appears to have been fixed. It was not a problem exclusive to Crossover.