If the current firmware begins with 072, upgrade to this one here and the option will be enabled for the space bar.
If the current software/Firmware begins with 071, I highly suggest a tech call be placed to have an Altboot no data backup no clone to those levels, the increment that changes from 071-072 is major, it is the change from Connectkey 1.0 to 1.5, and when done, due to extensive changes, does not at all play well with updates or clone files.