Many free phpBB hosts like forumer alter the original phpBB code to remove and change features that are normally in the original package. We do not support forums hosted by those companies.
To get this functionality, I recommend downloading and installing phpBB from phpBB.com onto your own web server. I'm not sure if forumer provides database backups, but if so you can then restore your current board's database into the new installation.
If you need some hosting, search google for a free PHP/Mysql host (that gives you a subdomain). Many have instant setup and while they require ads, if this is just a temporary thing to make sure you have the features you need, that shouldn't be a problem.
Also, you're welcome to test almost all of the functionality in a clean installation of phpBB by using the
demo. Demo boards are linked to your IP so you can't share it, and it gets cleared every hour. But it should give you a pretty good idea of what you can and cannot do on a clean phpBB board.