Current questions and answers regarding the map editor.

So, the function doesn't recognize the Fire Wave as a spell. You could try giving the hero a scroll or the Fire Wave itself at the beginning.

I tweaked it a bit in the editor, making it not related to SPECIAL, but related to the Destruction magic school. Now, when opening the map properties, it can be "assigned" to a hero. But there's still something wrong - during battle, the hero casts the Fire Wave and... nothing happens. No effect, no damage to the troops.

Added after 41 minutes
The same thing happens with the Devil's Chain.