OK, I will check the 64-bit version. The programs are written in Processing and exported using Processing as well. I am pretty sure we checked all platforms and made sure the updater program works on all. But you are right that the 32-bit version can work just fine on 64-bit Windows.
the ‘java not recognized as … command’ message means you need to install Java. You can go to java.com to download tne install Java. But before you do that, try the 32-bit version to see if that works.