Although your ongoing issue may not relate to incremental naming, the latter also causes losing rendered previews.

After cleaning up the Media Cache Database via Preferences within either AE or PrPro do not hesitate to delete remains in both Media Cache and Media Cache Files folders manually.

I gave up on the dynamic link thing pretty quick.  Cool concept but definitely not ready for prime time.  I just do the old render and import.  Then, if I have to change something in AE, I overwrite the previously rendered file with the new one.  That way it is immediately updated in PP. 

I see this behavior as well, sometimes just switching back and forth between the two pieces of software it will lose track of render files. It sucks to open a project a couple hours later and the dynamic link renders are gone, they are so incredibly slow to render as it is, I don't want to lose them.

I'm still on 5.5 and was expecting huge performance gains with dynamic linking when going to CS6, but from what I'm seeing here on the board I'm guessing that's not the case.

Well, the nature of the Universe doesn't depend on whether you are interested in hearing an observation or not. It just exists in the way it exists.

However, if you keep losing Dynamic Links after clearing up and rebuilding Media Cache Database, including clearing up Preview Files folder, and is still keen on resolving the issue, provide some more details on your PrPro project and linked AE one(s):

- what type of media files are used in the problem project?

- what is the order of building dynamic links for that project?

- what are the names of dynamically linked project(s) and comps?

- does the behaviour depend on which effects are used in dynamically linked comps?

etc. etc.

Meanwhile, although I didn't lose any Dynamic Link so far on my own projects and was able to reproduce and fix almost any voiced on the Forum issues with ADL, I can't be of 100% help since I'm still on CS5.5.

Well, with such sort of input data it's hardly possible to reproduce and accordingly fix your particular issue.

By the way, if you're communicating with the Universe by phone, it was a hoax I'm afraid, since we are on Skype for several years now.

You miss the first part of the sentence in the quote.

I would appreciate if you could point me out to those threads on the Forum, in which ADL issues were described in the same way as happening out of the blue with no pattern at all. I probably miss them.