RTF is a global modification that replaces all towns in the game.

.... I can't say exactly where you made a mistake, I just opened the DefaultStats file in the map editor and started adding abilities, spells, and other cool stuff. BY THE WAY, I managed to add spells, which wasn't possible in the original game, but the option was there, I hope there won't be any bugs.

Hmm, I tested it, and the active abilities don't seem to work at all. But the passive abilities seem to work, although some of them are unclear.
For example, adding Agility to a flying vampire always gives it a +2 bonus to defense; it seems the game only considers "steps" and not flight.

Thank you for working on this. Interesting facts pop up from time to time, and I need to think about new possibilities.