;D Ah the memories...well young'uns, let ol' granpa Wolfrug give you a lesson in basic mission.sqm editing.
Basic info: the mission.sqm is the thing which stores all the shiznats of your mission - triggers, units, waypoints and their positions and so forthwith. When you Merge a mission, what you're basically doing is copying the mission.sqm of the other mission on top of your current one. The file is notepad friendly, and not at all dangerous ;D
The deal: Open the mission.sqm of your mission (found in the mission's folder) and you will be met with a huge list of everything. What you need to do is find the police men in question. You will be met with something like this:
class Item4
   {
   position[]={6198.226563,2.274771,9247.783203};
   azimut=270.000000;
   id=126;
   side="EAST";
   vehicle="sebnam_nvmedic";
   rank="CORPORAL";
   skill=0.333333;
The important thing here is the side line: just change this from "CIV" to "WEST", "EAST" or "GUER" depending on what side you want them to be on. Easy as that, really. Then save the mission.sqm and load your mission. You will now note that your soldiers will shoot at the policemen and they will return fire. ;D
Note: do not try to open and edit anything on these modified units, or they WILL revert back to their "original" form. So make sure you've got all them names and init lines done and ready before you go editing the mission.sqm. Also note that you can copy & paste quite freely, so no need to go doing this on each and every one individually...
Any problems? Do share. :toocool:
Wolfrug out.