TY for keeping an eye out and uploading a scene should it crop up again!
I think the main point here is the way the thread on the forum reads, it's as if there is the same thing happening to multiple users, but this is not the case. It certainly appears to be a collection of separate issues (based on as much as we can tell, since we didn't get responses or didn't have scenes to investigate). And it may not even be a "memory leak" - e.g. the caustics example seems to be that it takes more memory in Corona 12 than in an earlier version, but this is not the same as a memory leak (which is the longer a piece of software runs, the more and more memory it consumes as it is not being freed correctly once no longer needed).
So, if this thread is one of the things that has put you off upgrading to Corona 12 because it reads like there is a common, universal, actual memory leak (since I have seen several people say they are not upgrading due to Corona 12 having problems, and I can only assume threads like this one is part of that assessment) - do be sure to asses things in the light of the above and not just on the first impression of reading the thread. So far, no actual memory leak has been found, and one issue of caustics apparently taking more memory than in a previous version is being investigated. Hope this helps!
