After tolerating the instability of ZR3 for a long time, I have finally decided to quit using the app. It has become unusable, crashing EVERY use at least once and causing other apps to force close as Android tries to frantically free up memory for the black hole that is ZR3. Six to Start have not even addressed this issue, even though they acknowledge it is a memory hog.
The resources I have made — the Google Music tutorial page, and the Bitbucket respository, will remain up for now, but will not be updated further. If someone wants to pick them up and continue with them, by all means, do so, and let me know, so I can add a redirect or link to your site.