Modding the spellbar

[dhoushi]

I've seen a few spellbar mods that turn the spellgem icons to squares. However I have not been able to figure out how to do this myself with a mod compatible with p99. The goal for this is to be able to use custom spell icons (both buffs and spellgems) at the moment, when I use a different spell UI graphics the buffs come out fine but the spellgems get all messed up.

I'm not looking for anything fancy, just something that will allow for square spellgems. Any advice tech?