Unable to tap options during installation, how to complete?

The feature 'tap to click' is by default disabled during my Mountain Lion reinstall, now I cannot finalize the installation. I use a Mac Mini with external Magic Trackpad. I can move the cursor on the screen and have 'tabbed' my way through the Disk Utility and installation process.

I have selected the destination HD to install OS X on and only have to press/tap 'Continue' to finalize the installation. However... somehow I cannot tap to click... When I tap on my trackpad, nothing happens. No tap, tab, or keyboard combination gets my mouse cursor to the button that will bring me to the next step. Also, I cannot activate 'tap to click' this early in the installation process.

Major bug, or do I miss something? No, I do not have a mouse in the house that I could use.

Help is much appreciated (or a mouse :-) )

(sorry for the bad picture, but my Mac Mini is connected to a TV)