What kind of trouble are they having? This was obviously designed to curb spam, as there were quite a few guilds getting auto-app-spammed before this was implemented.
My first guess would be can't read. Your design like most allows a link that says "unreadable?" and only changes to a new pattern. I was using a site with a similar antispam security feature and when you clicked unreadable it popped up a little embedded player like quicktime or media player and spoke the pattern. Just to throw that in.