Windows 10; LrC 12.1 crash when syncing from Lr on iPad and From Lightroom collections not updating
Now that I'm home from a long trip during which I backed up my images to Lr Mobile on my iPad, I'm syncing my photos to LrC. It has been very frustrating. Two major issues:
1. Collections in From Lightroom that correspond to Lr Mobile albums have stopped updating. The first sync sesseion worked fine and photos showed up in the proper collections. But after getting rid of some of the collections, the remaining ones are not updating and have zero photos in them even though the photos are in "All Synced Photographs". I've tried various techniques to no avail, including renaming sync.lrdata.
2. LrC has crashed twice. The first time it was at least hanlded with the bug report dialog box, but the second time was much worse as it appeared my entire computer was dying. It started by loud static coming from the speakers, then all three monitors went black. That lasted for about 40 seconds (seemed much longer), and then the screens came back and the speaker static stopped. On one of the screens was this

When that was acknowledged, another popup appeared:

LrC was no longer running. After a reboot I started LrC and it appears to function normally.
