Went to OF level 5, Wrathroot was there, dropped him. Went on searching for entrance to level 6 for the key and entrance to the lake.
The exit for level 5 is in the lower right hand corner of the map - meaning it occupies both a space on the right of the screen as well as a space on the bottom.
Looks like since the exit to the next level is on a bottom square, the code points it to the Lake of Nur. So I go straight from level 5 to the lake of Nur.
Now - going back from the Lake of Nur to the old forest via the entrance on the lake map takes you correctly to OF level 7, but places you in the top left corner of the map on a tree. You have to dig to the walkable area of the map. There's no entrance to the lake on level 7 of the OF.
You can find the entrance to level 6 off of level 7, and you get the same effect of appearing on the top left corner in a tree.
level 6 seems to map correctly to level 5, however again on level 5 itself there's no entrance to level 6, only an entrance to the lake of Nur.
Worst of all - no key ever appeared so I can't get my house