Upgradable Abilitys into clickable spells?

how would i make for instance flank cannons into a clickable spell.. i tried everything.. and it doesnt work.. is this possible and how would i get it to do that? i got it to work fine.. but it always works and doesnt take any mana or turn off. i want to make some passive upgradable abilits into spells so u can click on them like normal. how?

That sounds almost impossible. But you could create a dummy spell based on immolation, when it's activated, add the flakcannons ability, when it's deactivated, remove the ability.

I'm pretty sure any sort of solution will involve triggers and adding/removing abilities.