L@Zar0 was asking about this a while ago, and over in the forum thread for that earlier post, Kobra Kai Dragon provided one possible solution:

Pick up the chest, carry it to Daemon’s Crag and throw it onto the molten lava. The chest will sink, but the Tear of the Seas and other stuff will “ethereally” pass through the chest and miraculously float on the lava.

Granted, this doesn’t address L@Zar0’s question about Ultima 8 usecode compilation…but it does solve another problem he was having, which I gather is actually quite a common bug that many encounter.

So now you know. And a big thanks to Kobra Kai!