Problems after updating to wiki

I'm having two issues after the update:

1) I can no longer see the list of wikis. If I go to Wikis >> Wikis I just get a blank page. The other links (to Add Wiki etc) show the full page. I wonder if this is because I've got over 3k wikis in total?

2) I was linking the wiki with CustomPress to allow people to edit the custom fields I've created. However, this is no longer possible. I seem to remember adding some code to either the Wiki or CustomPress but can't seem to find it.

Thank you.