I think most people here use Atque
to manage terminal pictures. Atque turns a merged map into a directory of files and back, which makes it fairly easy to look at a working map and copy that structure to create your own working terminals.
For any future reference, this was eventually the way out of my problem. Atque proved to be a useful tool for reverse engineering how things are set up; Obed is a little vague on a lot of things, but ultimately works out pretty well. Obed wants you to insert each image which it reads as a level, and you call that level to the picture id under terminal editor. But getting a picture you've made to work is a whole other thing, and I believe I've run across threads on this forum which cover that.
I wound up giving Weland a go recently, being frustrated with the limitations of Obed (no ambient sounds?). I had trouble installing it initially and was too impatient to deal with it, but recently I just intalled it, it fired right up, and I've had zero problems with it what-so-ever. Much prefer Weland to Obed, although I wish it did more (visual mode, snap to grid, ...).