login to Cloudflare and then contact Cloudflare Support
Judging from your webpagetest link, at least it’s consistent across all three runs. The 522 shows the server timing out, which is odd since everything else looks good. I don’t use Rocket Loader because 1) As you’ve noticed, it can interfere with some aspects of a site, and 2) it’s unnecessary when running HTTP/2 (see below).
It also looks like you’re running WP Fastest Cache, correct? I use that one as well, but turn off all minification and such. Cloudflare can minify the same resources if you enable it from Cloudflare’s Speed tab.
I also use HTTPS. 1) It’s secure, and 2) Cloudflare uses HTTP/2 which does a better job of loading resources in parallel, though webpagetest only tests HTTP 1.1, so the benefits don’t show up there.