Day 7: Cupcake XY autohoming GCode

I'm trying to upload a Thing-a-day this February.
makerblock.com/2011/02/makerblock-thing-a-day/

I'm trying to create an auto-homing Cupcake CNC in an attempt to upgrade my Cupcake into a Thing-O-Matic. This "start.txt" file will allow your Cupcake to autohome. This code was essentially copied from the stock Thing-O-Matic autohoming code, but has been altered to exclude the Z homing (since I haven't designed an endstop for that axis) and does no heating of the extruder or heated build plat