By default the player window attempts to use a T10 potion. A variant of the window that uses the cureplayer behavior that would use your spell is included in the optional variants folder. Just delete your _Fetish_clickcures.xml file and rename the optional variant _nopotion_Fetish_clickcures.xml to _Fetish_clickcures.xml and move it into your main Fetish 12.4 folder.
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