MPC2000XL Hidden Screens (apologies for the tags but others were taking the pics without permission for their own pages)
Thanks to Rob Joyner of Australia for finding this!

From the main screen hit SHIFT + 5 (TRIM) then SHIFT + F1

From there you get this screen:

MEMCHK screen:


Clicking on VER gives you this:

From VER screen, click F6:

From this screen click on OPEN WINDOW and you get the "Easter Egg"

This was found by Rob Joyner of Australia!