I really hate to see this one go. I don't know what has changed but it doesn't block spam at all anymore, and hasn't for months.
I have used GASP for years and it's been great but about 6-8 months ago it just quit blocking spam. I don't know if spammers have gotten smarter (hint, they have. I've seen bot comment spammers for sale that can click "invisible" checkboxes like this easily), or maybe wordpress has updated and broke it. GASP has not been updated in a long time now and I don't know if it will ever be updated again.
I've maxed out the settings and played with everything but no luck. the checkbox is there, the other measures are there, I've changed my codes....but it just won't block the spam. With GASP running I get about 3-4 spam comments an hour on my high traffic sites.
I now use wp-spamshield without any problems. I really hope the creators of GASP bring some new updates in the future, I would love to come back because of the better options.