Hi Paul -
Ok, now that I know that your version of GB is GarageBand'11/Version6.0.5, some of what you're saying makes more sense. I found an older course on that version of GarageBand -- I've changed the link at the top of this thread to point to that course, which should correspond to the version you're working with. It seems to be a pretty comprehensive course, so hopefully you'll be able to find some answers in there..
- The section on the right of your GB screen is the same as the Library on the left in my version -- they just moved it and changed the name, but the functionality appears to be the same. In there you're loading preset chains of Track-based plug-ins, so I would think that what I said about accidentally changing [Real Instrument?] effect preset chains should apply in your version of GB as well
- I don't see any way to have effects tied to particular Regions on a Track [in either the older or current versions of GB] -- the only thing I see at the upper left corner of Regions is the Take number [which you'll see if you've recorded multiple Takes in Cycle mode]
Since I can't poke around in my version of GB and duplicate what you might be seeing/doing [and I don't think I ever used that older version of GB], I can really only refer you to the course on the older version -- maybe check out video #63 [Insert Effects] and video #70 [Automating Effects]..? In fact, Automation is the only way I can think of that you could have different/changing effects at different times on the same Track in GB, but, again, that could be a version thing -- but hopefully that GB'11 course will be able to clarify a little..
PS - The Forum does seem to have some odd restrictions on characters at times -- I'm told it's due to the aggressive anti-spam software in use..