I've got a '98 Disco 1 and can't seem to figure it out either.
My GMC/Cadillac homelink is simple to program and works great.
This Disco homelink, however, won't work on my garage doors, unless I'm doing something wrong in the programming process.
its listed in the owners manual. you have to clear the old programming first, i dont remember how to clear it. to set it after cleared though press the 2 outside buttons until the light is flashing then hold your remote against the homelink unit and press then at same time press the button you want homelink to remember and it will b programmed
like i said...
my Cadillac works fine.
my Disco 1 homelink won't "take" my garage door.
so I'm screwed.
unless I'm willing to take my vehicle to the dealer who will charge me $100/hr. labor and $500 in parts for something that may work perfectly well right now.