The plot isn't bad, but a few other things need work.
First, we didn't hardly need any of the title screens, yes, the first one or two to set the location maybe.
But all those in between each person getting the meals and jumping were not necessary and messed with the pacing/flow. The dialog and actions were clear enough without the forth-wall breaking text.
Try simply cutting next time.
Second, mixing fleshies and yellows. (Horror of horrors!)
If you have a limited collection, then yes, mix the two. But don't mix on a figure.
Both fleshie girls had yellow on their bodies, and the yellow girl had flesh tones on hers.
When every other figure is straight yellow, the above creates discontinuity, and pulls folks like me right out of the story.
Now, the set was decent, but micro-scale buildings, or more girders connected to the one they're standing on would have help fill out the set. (Of course, it's THAC, so that can slide.) The funeral home set looks nice, and I like the coffin designs. The voice acting is pretty good, and the punchline is great. The animation could be better, but first THACs are always stressful. It's nice to see you try it, and I hope you enjoyed the whole thing.