Where did you get the board? If you got it from Printrbot, they should have configured it correctly for your printer.
The bed dimensions are probably available to you in EEPROM and can be changed. For setting your bed size and probing locations there are several threads in this forum. For one example of many, see viewtopic.php?f=15&t=11191#p71893
As to loss of communication, it's possible that your new board maps to a different COM port address than the old one. You can easily find out the correct address in Device Manager, and then set Cura or Repetier to use that address.
Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick