I think you will find the majority of people would want to use this simulator to fight on a campaign map.
I can foresee the kind of problems that could be caused with units trying to find their retreat path etc?
But, this would be a fantastic addition to reflect what is happening on a campaign map, ie reinforcements to be able to enter the battlefield from any direction to reflect armies/corps/divisions being cut off from their line of retreat/communications or surrounded.
I know somewhere in the past you have said about a campaign feature, but this would be the icing on the cake if we could mirror what was really going on in a Napoleonic campaign, ie lines of communication being cut etc.
But if it is not possible it is not possible...