Thanks very much for the screenshots. I have a couple ideas that may get you past this, even if I'm not yet clear on what's exactly happening to cause PD to not accept the linked clips.
First, copy a clip with the original soundtrack and place it on the timeline in the New_Sndtrk project. Unlink the A/V on both that one and the matching one with the new soundtrack, then swap soundtracks and try to link again. This will tell us whether the issue is related to the new soundtrack or not.
Second, go back to the step where you first had the 2 long clips with the new soundtrack, then produce each one (search the forum for
Produce Range if you're not familiar with that process). If doing that AND repeating the cuts you made aren't too much work, that should solve your problem.
There's actually a way to get your New_Sndtrk project to open up with those new clips rather than replacing them all on the timeline, but if those clips aren't recognized as "whole" that may not work, so for the moment just think about whether it's worth redoing with produced clips.
Another option would be to use the
Pack Project Materials feature to save a copy of the project and all its media files in a folder, then upload that to the cloud and paste a link here. That way I and others could open it up and see exactly what's going on.
Go with as many of these as you're comfortable trying out.
YouTube/optodata
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