I'm editing a bunch of clips that are sped up, so nesting and then adding warp stabilizer at 10%. Every time after rendering the stabilized clip, the beginning of the clip directly after the one I was working on has an imprint of the previous clip (about two frames long), however the image hasn't been cropped like the stabilized one. So the result is a jerk out movement in between every clip. I can crop it off the front of the affected clip but it's time consuming, and I'm editing to music so it's ruining the carefully placed cuts. How and why would this happen? Any help would be hugely appreciated.
I'd need to watch you in a screen recording to really see what's going on. The mistake I'm envisioning may have something with the way you are marking and/or selecting clips that go into nests. Can you make a recording and upload it to YouTube or place some screenshots here, at least?
One thing to always remember, and it's not obvious. The CTI ... the playhead ... is always connected to the next frame, not the one before.
So if you go to the end of the clip and mark out, the playhead is actually "connected" to the first frame of the next clip. So the out point includes the first frame of the next clip.
You can either hit the down arrow (to go to the end of the current clip, really the next edit point) then left arrow to go back one frame. Then hit the O for out point. You get used to it, it's fast ... bap-bap-bap in maybe a half second.
Or ... go to the Keyboard shortcuts dialog (Ctrl/Cmd-Alt-K) and type "go to selected". Then where the keyboard short says "go to selected clip end" set a keyboard shortcut. That one will always set the playhead at the 'front' of the last frame of the clip, so setting out point then only includes that clip.