Mmmm... Maybe that happens because in Donum there is both a box and a moneybox. I'll check it out.
Thanks for your words!
English & Spanish demos are the same, the only difference is the text.
The corruption you're talking about is known as "snow effect". As you said, this effect (not a real problem) was fixed in Donum_ENGv1.1.tap. Anyway, such effect do not affect the functionallity of the game, it's just an "effect". More info at the development log.
Night four? That's great. Cheer up!
Donum was programmed using a mixture of Boriel Basic (compiled), assembler and the ZX0 data compressor for text, graphics, music and some code... The chosen decompressor routine is very fast, almost in real time.