I found an issue that only appears to effect the main site, but not the sub sites when membership is active. I only had membership active on the main site not any sub sites so I'm not sure if it effects only sites it is active on or just the main site.
I was trying to write a new post and every time I clicked on text view nothing happened. I thought maybe it was just the browser, so I tried another and had same issue.
I noticed another issue, I was trying to create a hyper link in a post and every time I clicked the hyper link icon my scroll bar on the right disappeared.
I tried to disable some recent plugins and nothing changed, then I decide to try Membership since I only have a few plug ins enabled and when I disabled it everything worked correctly.
I've enabled support access if you need access to anything else just let me know!