Hey guys! I don't know if this is what you guys mean, but I was having a similar issue, where when I trimmed parts of a region and then delete that new region I trimmed, the remaining regions would automatically merge. It was driving me nuts! The Solution after a lot of research was I had "Shuffle L" selected on my drag settings. On the main bar the little "Settings Gear Icon" you'll have "Snap" or "Drag" settings. Go into "Drag" and switch from "Shuffle L" or "Shuffle R" to anything else you want and you're good.
Hope this helps!
God bless!