Charge Gold and Lumber, buggy?

This ability appears to me to be rather buggy. The tooltip text seems to always refer to level 1 text, it doesn't respect cooldown, and leveling it up beyond max level is not prevented.

The only event it emits is "Starts the effect of an ability" and if I catch that and increases the level of the ability, then it will charge the amount for the next level. I.e cast level 1 which charges 10 gold, catch the event and increase the level, and the player is charged for the level 2 amount, ie 20 gold.

The obvious workaround is to have a tiny wait before actually leveling it up. Being paranoid, I would also then have to make the triggers check that no-one are able to cast it again during that tiny wait. Just seems like slightly cumbersome.

I post this mostly for information as I didn't manage to dig up any info on this myself with a forum search, but if anyone has any suggestions for how to deal with any of the problems that would be appreciated as well.