The return parameter that I can see on your page is:
aW5kZXgucGhwP29wdGlvbj1jb21fdm12ZW5kb3Imdmlldz12ZW5kb3Jwcm9maWxlJkl0ZW1pZD00Mjk=
Which, yes, is gobbledy goop. But, that translates to:
index.php?option=com_vmvendor&view=vendorprofile&Itemid=429
Does that look like the right page you've configured in the SCLogin module for the redirection? If not, please update that setting. If that is where you want it to go, I'd suggest the following:
* Set the redirection to a different menu item and try again. That will just help narrow down if the problem is on all menu links, or just that one.
* Disable any SEF extensions (or core Joomla SEF) and try again. Even combine with the suggestion above.
Between those, we should be able to narrow things down and get you fixed up.
Thanks,
Alex