In healbot options - - Skins - Frames - General - select the frame that you use for raid groups - then in the centre right hand side - Frame anchor - should be "top left" for you I think - one of these options on the right hand side is probably set wrong for you..
Hope this helps.
I'm not sure what option you are at to be honest.
Short answer is to go to the bar color picker - select the color that is active and click on the bar color - this should give you the color picker panel - set the visibility slider on the right hand side down to the max minus and the border will disappear.
Hope that helps
Go into Healbot options - Skins - Frames - General - Select the Frame you need to change - Middle of panel "Frame Anchor", select Top Left - and the frames will grow from left to right.
Hope that helps.