Hi Coding,
First of all, thank you for this brilliant system. As a member of a GU with a dedicated artillery/mortar section, this is the exact sort of thing we have been looking for as a replacement for the vanilla artillery computer.
Everything works well apart from one bug. If the map (such as Stratis) starts with grid squares labelled 000 etc across and up both x and y axis, the system works brilliantly. However, some maps, such as Chernarus, do not (the Chernarus y axis starts 153 and ends at 999). Using Chernarus as an example, if I set up a mortar exactly at the Altar trig point located at 0814 0628, when I use your computer with the GPS enabled (to give me my position automatically) it comes up as 0814 0913 even though my GPS on the normal map shows the correct position. Therefore, any target locations you give it will mean the computer will calculate to somewhere else entirely.
I hope this is something that is fixable as this is an excellent mod when working on the vanilla maps!