Just found the SoapSkinBubbleTool and it's a little different to stop toolbar opening every time.
In the plugins folder there's a folder called SoapSkinBubble, and in there is a file called SoapSkinBubbleMenu.rb. Edit that file and find the line:
sbToolbar.show
and change that to:
## start troypiggo edit
# sbToolbar.show
state = sbToolbar.get_last_state
if (state == TB_VISIBLE)
sbToolbar.restore
end
## end troypiggo edit