The latest version should work fine for any version of Windows greater than 95. (It may take some playing with the font to make the notes show up correctly.)
Right now our biggest issue is getting help, since we haven't had time to work on this for a while now. The biggest technical issue right now is that you need the '.dcl' file in order to compile with Delphi, and it doesn't yet work for Kylix. All the source is there if you would like to try it out. I hope we can get it to work for Kylix so that we can develop it for Linux.