To skip levels, go to map screen and hold down control and type Fodder.
A white border will appear around the screen.  Exit map and return to game.  
When you press enter, a message will say 'Phase Conmplete' signifying
the end of that level.

Some saved game hex editing:

Offset  Valid Values   Description
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 00       00-47        Current Mission
 0C       00-23        Show mission brefings
 48       00-FF        Kills by leader
 4C       00-0E        Rank of leader (00=private, 0E=general)
 58       00-0E        Rank 2nd
 64       00-0E        Rank 3rd
 70       00-0E        Rank 4th
 7C       00-0E        Rank 5th
 12       00-FF        Number of recruits
 6F2      00-FF        Number of kills