People please be a little more helpful if you're going to post a reply :). And Electro, that little melodrama of yours was hilarious "Alas, the heavens will cry forevermore the hallowed namesake of Scio" :P.
Alright silvery, here's what you do. Start up the unit editor when you've opened UMSWE and your map. Create your new custom unit or find the unit you are going to change into the eggsack. You'll notice that with UMSWE there are a number of text files in its main directory. One of them lists every model in the game (including doodads and special effects). Now, to save you the hassle of finding them this time around, the doodad models are:
Doodads\Dungeon\Terrain\EggSack\EggSack0.mdx
Doodads\Dungeon\Terrain\EggSack\EggSack1.mdx
You can choose which of the two you want, I'll let you :P. Anyway, open the model used dialogue. You'll notice that the entry is now a string value instead of the panel that pops up in normal WE. Paste your chosen eggsack model into the space, and then get rid of the ".mdx" at the end of it. Ie. If you choose the eggsack0 model and clicked ok, you should see:
Doodads\Dungeon\Terrain\EggSack\EggSack0
Tada! That's it. Easy as pie.
~kharma | 
