the problem is, that vbulletin wants to send you back to forumhome. and normally you cannot link your logo to anything else. unless you modify your template.
with the changes in 4.11 our trick to replace the forumhome url with index does not work anymore.
so the best thing to do would be to set in ACP=>vbgallery=>modify layout
the logolink to default link (Like in forums)
this should work, but it will then behave like in forums. (It works for me but I use absolute links)