Hi Kurt,
Yes, you are right on the spot there. Being a trunk version, it can be unstable at times.
A few months back, when I was using the open source code, I found it very tedious and just waiting for my failure to remember to do the backup. For a while I then had two folders, one for testing compilations and another for the real thing. Every time I did an update, I did it first on the test folder, and if that worked, I proceeded to the real one.
Later on I started trusting the restore points / previous versions on my Vista. I just updated, and if it didn't work, I restored a previous version of the folder via Vista's "Previous versions".
Palli