Cache files corrupted

Caches are known to be fragile. That's why there's always been the ability to Purge caches so they can be rebuilt. I suppose it's possible that the new Bridge "broke" the current cache, but I personally find that unlikely. What's more likely is that the old cache was already in a bad state, and the new bridge was able to determine that better than the old cache. 

But, simply, caches are just a saving of information to speed up subsequent viewing. If anything, I'd be grateful that Bridge warned you that it was in a bad state and needed purging as opposed to giving you grief about the bad presentation of your files and your not knowing what was causing it. 

Consider this a good thing instead of a bad thing.