Hey Vera, I'm pretty new to the scripting side of Flashpoint, but I do know how to do the Map-Click Feature:
Put down an empty marker on the map and call it "target". Then, in the script, put:
OnMapSingleClick {}
_pos = _this select 0
"target" setMarkerType "destroy"
"target" setpos _pos
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then you tell the artillery to target the "TARGET", then tell them to fire on radio command. :gunman: