One more issue is that nodes appearing on multiple pages are listed multiple times,
this is however possibly a feature, but I am trying to configure or program it to only show once per unique node. (the first in the cat_list I guess.
I think there's not a good way to avoid the problem you're having
without some code. That's because there's really no way for solr to know
in advance whether the current user has permission to view the node.
You have to basically ask solr the question, "What nodes match the
search query", and then filter the result set through
node_access('view') or mm_content_user_can_node(). Of course, that
presents problems for pagination.