Thanks guys! I am back up and running (fingers crossed!) after 7 hours of restoring tray structure by hand. Yes, HIERARCH.PM seems to contain bunch of suspiciously looking lines. Fortunately I found a description of its format here:
There is also important tidbit here:
Will have to work on it. Also I have a bunch of old folders still in UNIX format, so that might have contributed to the restoration trouble. Just documenting my experience in hopes that it will make someone's life easier.
Happy Thanksgiving everyone!