We have our (many) layouts all in folders.
However, as you scroll down the list, in layout mode, at a certain point, it stops showing the folders, and just shows the raw layouts.
In Manage Layouts, everything is fine---the folders are there and work.
I had thought this was due to corruption, but I talked to some other developers who also had the problem. So, I am reporting it.
I have seen this since version 11 through 14. Windows and Mac. Various Mac OSes, various Windows OSes. This happened back when we had, say, 500 layouts . . .now we have over 900, and it is still the case.
I'd be happy to send FMI a sample clone of the file.