Thanks for your kind comments, and for the tip on BFXR, I'll check that out.
Re your experience with the Wyvern, I suspect a problem with the random generator as it seems to produce long sequences of high or low numbers. Certainly the chances of failing to kill a Wyvern after 26 attempts should be vanishingly small. Choosing a better generator will be on the list of post-jam revisions I'll be making to the game. I've put a warning in the game description for now.
Re the engine, yes I hope to make use of it for other games. Problem is knowing where to publish very retro stuff like this that has niche appeal. DCJam is great but its only once a year and the prospect of releasing stuff ad-hoc here, or even on Steam, feels like that scene at the end of Raiders of the Lost Ark!