This looks like part of you code.
http://www.melabs.com/resources/samples/x1/pbp/keyx.bas
and here is the schematic for it
http://www.melabs.com/downloads/labx1sch.pdf
Make the necessary hardware changes and get the above code working. Do not add anything else yet, just the keypad code. (maybe a blinky to see if thing are running) but nothing else.

Then we will go from there.