Yes - I just put up a site on Expression Engine 2.3.1 that I just started running through Cloudflare. Just now it’s decided to start logging me off at random intervals but usually after about a minite. It’s not browser specific as I’ve tried in Firefox 10 and Chrome.
Some of the publish forms were also busted, not allowing me to go to different tabs. I disabled Google Webmaster alerts/ tools and Google Analytics that I had activated through Cloudflare apps and that seemed to sort the publish form problem - but not the random loggin out.
Would be really interested to hear if you managed to fix this…