Is the forum working or is the problem related only to my account?

Hard to say without knowing more. Which post it is? And what is the content of your message?

If your attempted post contains mismatched quote tags the forum software will silently fail to accept your post. There might be other reasons too, but I can't remember any other right now.

The only thing I think we have a certainty is the question about it being related to your account and the answer is "No"

There are also mousetrapped phrases that will be triggered if you use them, such as N ew Y ork U niversity.

It's strange to me that a forum only fails for a certain user at a certain post replying to a "blue" user... but anything is possible. The message ended up appearing some time later.

That sometimes happens when your post goes on a new page in the thread. As your post here did: https://www.gog.com/forum/general/i_just_joined_nothing_is_working_at_all_downloading_installing_loading/post41

These forums have lots of annoying little bugs like that.

Then it was just a minor issue. Thanks for claryfing it for me.