OK, I know that this is not a bug from your side, but from the skin's side. But I am hoping you can perhaps guide me to the correct place to fix it. On some of my custom skins the pop-up (See attached) is transparent. Where is this controlled?
I have Firebug installed, but please, I just spent hours looking for this. I mean, you guys wrote this, is it so difficult to just tell me what CSS You are using for this?
You need to either add the right details in the style attribute (i.e. <div style="border:1px solid none;">content</div>), or you need to change the class (i.e. <div class="something">content</div>) to something that contains the background content you want.
The alternative is to revert the CSS style in the StyleVars back to their original. If you can post the content of your CSS that applies to that section here, it might help us debug.