I don't have a keyboard remote to try...but the normal way is to use the arrow/select buttons to type what you want.
Roamio Pro, wired ethernet
Mini using MOCA (from the Pro)
on Cablevision Raritan Valley system (Central NJ)
w/ Cisco PKM803 CableCARD on firmware 18.104.22.1681
*** 2013 newbie to Tivo ***