Have you been logging in to the 'Play Game' tab (Located on the thing with 'Staff', etc), or just the forums
You need to click on that, then log in there, wait 20-30 seconds, log in to FeralHeart, and it should work.
Keep in mind, sometimes the login page is a bit pesky and logs you out. If that happens, use a thing like 'refreshthis.com' and set it to refresh every few seconds.
Hope I helped you out!