Thanks!
Yours was one of the first "new Retro" DOS games, I think. There are some similar efforts even today, such as Anzu Castle Gracula and Gold Miner.
DOSBox Staging actually had trouble with Anzu Castle Gracula until a recent DOSBox update, so it seems like some emulators are having trouble with new homebrew. (Makes sense, since DOSBox forks would not have been tested very much with new games).
386 is available to me, so maybe this will be tested eventually. I just learned of your 3D Dungeon game, and my hardware is just enough to meet requirements!
I found out about Viana in a 'history of CGA' topic somewhere. There's been a lot of questions about CGA recently - why it was the way it was - and they are being answered.
It's really great that you made your games actually run on classic video cards.