I am also having this issue.
Right-clicking on the unit frames opens up the pitbull config. menu and not the usual drop down menu I was expecting.
When using Clique, I bind spells to right click, Alt + right click , Shift + right click, and ctrl + right click but disable their functionality on the player, party, and target frames so I can still(in theory)access their respective drop down menus.
However even upon deletion of the click-spell bindings the problem is not resolved. Right-clicking on the unit frames will still continue to bring up the pitbull config. menu until I reload my UI.
Also... is there a way to just disable the click = config menu functionality?