Luís,
Sorry for the forum issues, if you noticed them. There's a weird glitch with our forums that we fixed months ago, but users that registered before a certain date can still run into the problem. You shouldn't have it anymore though.
As for your issue, can you check the "Activity Log" for you user and see if the action was posted there? Facebook decides whether the Like should show up in the user's feed depending on multiple factors, and not all actions show up there. If the user chooses the "Publicar no Facebook" option, it *should* show up in the feed, but even then, Facebook can choose whether it will show or not (based on relevance to the viewer, popularity of the link - other user's who have Like'd it, and other factors).
So, check the Activity Log (in your Profile view, the link is directly under your cover photo on the right side). If it's not there, let us know. Just so you know, we just like'd an article about Hurricane Sandy on your site, and it took about 5 minutes to show in our feed. That's a lot longer than normal (not sure why), but it did work.
Hope that helps!
Alex