Ok this is going to be a bit of a laundry list of items here but there are a number of things that are problematic.
The first is that messages are not being marked as read. I have added a page rule to cloudflare to bypass caching on the following URL which is the base of my forum installation: http://vikefans.com/forums/* .....ditionally it looks like the PM's are not sorting correctly. It appears that it is sorting by the first PM date rather than the last PM date.
The next issue is that for some reason everyone including admins is getting a security check failed when trying to post polls out of the blue.
The final issue is that I cannot complete an update of the forum software as it fails and then leaves the forum deactivated. I go back and reactivate and everything seems fine but I cannot get it to update correctly.
As far as upgrading the forum software this is what I get when trying to run the upgrade:
The update process is starting. This process may take a while on some hosts, so please be patient.
Enabling Maintenance mode…
Updating Plugin Simple:Press (1/1)
I don't personally know enough about Cloudflare to pass a verdict on whether a simple url rule is enough to stop it. I DO know people have had many issues with it in the past and turned it off altogether. The important part of the question would be was cloudflare in use when these things were not happening. And if the answer to that is no then what happens if you turn it off totally again?
As to JetPack I do not believe it comes with any caching but it does come with an awful lot of junk that is turned on by default. Sadly - as it comes from the Automattic stable - it is notoriously problematic. But I think we should follow the caching question first.
well, there are folks that run cloudflare okay (see posts from @fidosysop-2 where he talks about config) but like any CDN its very sensitive to configuration for sites with dynamic data...
but I am seeing many js errors on your site... mostly that content is blocked... like infolinks and other... its running cross site scripts (not really cool)... not sure if affecting site, since I cant do much as a guest...