This seems to be a permenant problem with MPLAB now.

So with PBP 3.0.7.x and later, all [303] messages will be suppressed on the Enhanced core devices.

If you are getting the "Program word too large. Truncated to core size." messages ... update your version of PBP3.
Or, Even if you're not getting those messages ... update your version of PBP3.

If you already have PBP3, the updates are free. So keep it up to date.
http://pbp3.com/download.html