Today the database was moved to an exclusive database server which its RAM will be increased if it is not enough.
Forum has been upgraded to Simple Machines Forum 2 series.
And that update has let me enable the forum registration via email activation. This makes me unnecessary to approve every registration.
If the captcha and the two simple verification questions are not enough to stop spammers I will try to add some measures that disable access to well-known spammers.
Just enjoy the improvements. The database migration should imply a better web experience.