A possible (partial) work around; Teleporting Anywhere, via hex editor

Once you get past somewhere you can use your teleporter stones to get out, but doing this repeatedly would be a pain.

Boratus' cellar
X = 80 1D ; Y = D0 A7 ; map 02 - at the stairs
X = A0 1E ; Y = 30 A9 ; map 02 - in the cow's cell