The recipe can be changed back in the config.I found 1 in my previous world (Mindcrack), I'm not much of a caver though. It was from a regular zombie spawner close to the surface.
In the worlds before that I made them myself, but back then the recipe didn't require a Nether Star. So yeah, since the recipe change I haven't seen much portal action outside creative.
Did you have to do anything special to switch your world from DW20 to Ultimate? Or did you simply have to move the save folder?4 portal guns
didn't know it possible to find spawners in chests, i updated my DW20 to ultimate and i didn't explor so much.
Heh. I just Uncrafted a gun and got some portal spawners. Nice.4 or 5 guns, no portals so far.