Yes I get the same invalid URL error if I try to edit anything then save. Nothing is saved from the vbshout ACP just get that error.
But the shoutbox works okay.
I have it in a module under the Welcome module, and the shoutbox tends to be very w i d e , s t r e t c h e d out. I mean it looks weird no matter how wide you stretch the browser you still don't get to see the right side (end) of the Shoutbox module.
See, it doesn't look right, it works, but it sticks out like that at the edge of the forum, always looking cut in half.