Thanks much Dan. Having no MEFCacheBackup shouldn't be a problem, I think that is just the original name of "ComponentModelCache", which was renamed in a later version of SSMS16, and I just had it lying around from an earlier install of SSMS16.
As I think we already discussed over email, if ViEmu does enter normal mode with the block cursor, it means that it has loaded correctly, so the problem solved by clearing the caches is not happening for you. That is good.
On the other hand, ESC not working later to go back to normal mode means some piece of code is "gobbling up" the event and not passing it down the event processing chain. Some third-party add-ins have been known to do this in the past, especially in VS, and since they think they can handle ESC completely by themselves (as it does little else in stock VS than close a code completion drop down and maybe remove the current selection), they don't worry about processing it correctly.
If you send me the list of third-party extensions you have installed, I will try to look into it and see if that is the case, and then try to find a work-around of some sort.
Regards,
-- Jon