My patched version can be found here:
http://www.wothke.ch//flashmod/Cube-O-Matic.modAs compared to the original file, a default speed now initially is set for each voice, i.e. the file no longer depends on some undefined global default speed. The file should therefore play with any .mod player.
I set the speed based on the following calculation: PI*guesstimate. You can easily change it using some tool like OpenMPT.