Some users of cpnhelp.org have reported difficulty creating a new forum topic or posting a blog. The site seems to like some browsers better than others. I'm a Mac user, and sometimes Safari doesn't work so well, but Netscape does fine.
Another thing to try if you are having difficulty posting things is go to your account settings "My Account" and "Edit" and turn off the "tinymce" setting. You won't have the buttons or smileys to use, but see if that works more reliably for you.
If you have difficulty, try this, and let me know what works and what doesn't: specify PC/Mac, your browser, and whether it was a forum, comment or blog.