Yes, FREE!ship will work with Windows 7 64bit without any issues. I've downloaded the executable file (it's delivered in an archive) and launched it on Windows 10 64bit. It works and I was able to create something in the software. All the functions are working, plus there were no errors shown on the screen when I used and launched the features.
When launching, right click the executable file and choose Run as Administrator (this is in case you want to save the files to the system partition).