I use this CAL on virtually every project to split my drums out to individual tracks. You do not need to move the source track to the last track in the project. When you specify the target track number in the script just specify a track number that's several numbers higher than your last track to prevent the created tracks from obliterating any of your existing tracks.
I don't have any issues w/ instability w/ this CAL.
Other tips:
-Don't worry about selecting the source track before running the CAL -- you specify it in the script.
-Take note of your source track's MIDI port before running the CAL. You are asked for it in the script and setting it correctly will save you fixing it up in all your created tracks.
- I always set the MIDI channel to 0.