SUBSIM Radio Room Forums - Power of the machine gun?

Open Mission Editor
Click on 'File' => 'New Project' in the top menu bar.
In the next 'New Project' popup window, enter any Name and Location on your HD where your mission will be saved. For my example I will use "test mission" as project name, and "C:\Users\Gabriele\Desktop\test mission" as location. Click 'Ok' when finished and a world map should appear in the main window.
Click on 'Campaign' in top menu bar, move the mouse over 'Player side', and select 'Axis' in the following drop-down menu.
Click again on 'File' menu => 'Add New Mission', or alternatively press the Ctrl N keys.
In the next 'New Mission' popup window, enter a Name and select a Start Date. For my example I will use again "test mission" as mission name, and I will select 01/01/1940 as start date*. Click 'Ok' when finished.

NOTE: make sure to select a date within the timespan that the nation of the ship you want to test was in war with germany, or the ship won't fire on you, and game will ctd if you sink her. Check the diplomatic position of the various nations from data/Roster/DefSide.cfg
Time to place our sub: in the 'Explorer Window' (top right corner by default; switch it on from 'Windows' top menu if not visible), select the 'Sub' tab, expand the Roster => German and drag/drop on map one of the following units:

Type VII-A
Type VII-B
Type VII-C
Type VII-C/41

NOTE: don't pick the subs marked with the (IA) suffix, and make sure to drop the selected sub not too close to land, or the mission won't pass the validation (see below). In order to measure distances in ME, you can use the ruler (click on the button displaying a stick with the 12 number, on the top left corner, and drag the mouse on map while holding the left mouse button pressed; click again on the ruler button when finished, or you won't be able to select anything on map).
Now we will set our sub: click on it, and its properties will appear in the 'Properties Window (left side of the screen by default; switch it on from 'Windows' top menu if not visible). Under 'Group information' => 'Commander', select HUMAN. From the same window you might want to change (optional) other parameters such as 'CurrenSpeed', 'Heading', 'Height' (i.e. depth), 'VeterancyLeve' (i.e. crew's experience), 'SecondaryEquipment' and 'MainEquipment'
Now we are ready for adding an enemy unit. In order to do it we will follow the same steps as when we added our sub: 'Explorer Window' => 'Sea', 'Sub' or 'Air' tab => expand roster, and drag/drop on map the wanted unit.

NOTE: make sure to drop the selected sub not too close to land or to other units (including player's sub), or the mission won't pass the validation.
We need to give the new unit a set of waipoints to follow: select it and right click everywhere on screen, select 'Add Waypoint' from the following context menu, and click on map as many times as you want for setting waypoints' position. When finished, right click again to end the waypoint setting mode. Finally, you should select again the unit (it is the diamond marking its starting position), right click and select 'Head to Waypoint' from the context menu: the unit will be oriented automatically for facing toward its first waypoint.
- Optional: you can click on any set waipoint for setting (in 'Properties Window') unit's speed until the next waypoint. If you want the unit to loop between waypoints, you can similarly select the last waypoint, and set its 'LoopProbability' and 'LoopPoint' (i.e. the waypoint that the unit will head to, once the last waypoint is reached).
- Optional: you can edit unit's properties with the same method used for player sub properties.
- Optional: creating convoys and task forces:
  
  - select the unit you want to behave as the leader, right click and select 'Create Group from Unit' in the following context menu;
  - create then as many new units as you want to be part of the convoy. You don't need to give them any waypoint, as they will follow their leader;
  - once finished dragging the new units on map, select them one by one, and in the 'Properties Window', under 'Group information' => 'Group', assign them to the recently created group (by default groups are called "Group Name1", "Group Name2" and so on, but you can change their name by editing leader's 'GroupName' property);
  - after assigning the first child unit to the group, the diamond denoting its leader will be inscribed in a bigger diamond. When all the child units are created and assigned to the group, zoom on the double diamond in order to be able to select its leader alone; do it, right click and select 'Arrange Group' in the following context menu;
  - in the following window, you can set the number of columns and the spacing between units and columns. When finished click 'Ok', and the convoy will be arranged automatically :up:
  
  NOTE: You can group Sea/Sub units together. Probably you can create as well groups of aircraft, but don't group ships/subs and aircraft, or the latter will try and fly at the same speed as ships, crashing miserably :yep:
- Optional: editing mission settings:
  
  - in the top menu, click on 'Mission' => 'Parameters', for editing
  - leave 'Mission Type' set on 'Single Player';
  - I don't know why there's another setting for 'Start Date', but usually I leave it unchenged, same goes for 'Mission Start Delay (days)': leave it set to 0;
  - more interesting for our pourposes is the possibility to change Star Time and weather setting;
  - When finished click on 'Accept'.
We should now give our mission a title and a description to be shown in game: in the top menu, click on 'Mission' => 'Language Localization'; in the appearing 'Language specific strings' window, select 'MissionBriefing' and type whatever you want in the empty space at the bottom. When finished do the same for 'MissionTitle' and click 'Ok' to confirm your strings.
In the top menu, click on 'Mission' => 'Validate Mission'. In the following window, click on the 'Check Mission' button. If, as we hope, everything is okay, the upper part of the window will show the text "Mission Title :" followed by the title you have typed in the previous step. If ME detects a problem, you will be given the details of what is wrong with your mission. If needed, read back this tutorial, correct the mistake(s) and repeat the current step.
Last: menu 'File' => 'Save As Game Mission', taking care of giving the mission the same name as the folder where it will be saved: "test mission" in our example. The final result should be a 'test mission' folder containig the following files:

test mission.tsr (mission's name and briefing)
test mission.misge (mission's settings)

You can drop the above folder directly in data/SingleMissions or set it as you would do for any other mod, in order to enable it with JSGME.

LAST NOTE: afaik, once you close Mission Editor, you cannot reedit a custom mission in ME, but you can open the misge file with notepad for editing its parameters (enemy crews experience, weather type, etc)