First step is to get your map to show a preview when looking at it in the load menus (load map, load scenario, play scenario).



To get this, you simply load your map into the map editor - this is what it looks like before we have an image:

Once your map is done, press "h" to bring up the camera tool:

Scroll the map and zoom in/out to get the view you want to use inside the square, and press "h" again. Save the map, and it will now appear with an image in menus:

Now that your map has a preview, you can load it into your scenario and build your scenario design.

Once you are done, save your scenario.

Now go play your scenario. Find a nice spot to showcase it, and do the "H" steps again (as above).
Now save your scenario. This step is important to do while in PLAY mode - otherwise you won't get a background in your workshop image.

It will show up in the load scenario screens with the new background from your map.

Now, once you have tested your scenario and are ready to share, you can "upload" it to the workshop and it will appear with the national character in front of the preview image.

If you have already uploaded it without the preview image, you just need to edit the scenario again and "update" (after doing the H step while playing it). This will load the new image - Joy !
This will take your workshop entry from this:


to this:

Once you have your scenario in the workshop, you can then go edit the workshop entry to add screen shots.

Take some while playing your scenario by pressing F12 for full screen. You can find F12 screens by using the mange screenshots function on the steam library page so you know where to upload them from.

You can also use H while playing to get just a part of the screen.

But you will need to be aware that SF will only save 1 H image at a time, overwriting the previous one. If you want several of these, you will need to manually copy the file out after each one. You can find where they are stored using the Steam library function to browse local files. They are in the ...\Second Front\Second Front_Data\StreamingAssets\Pictures folder, with the name matching the scenario name.

Once you have your pictures and know where they are, you can then attach them to the workshop entry. Show some interesting spots that you want to highlight on the battlefield!

Then open your workshop item and look at the owner controls.


You want to use the "Add/edit images & videos" function. On the page that opens use the upload control on the left to load your pictures.


You add them one at a time, and when done they will appear at the bottom of the window.


Click the "Save and Continue" in the lower right when all pictures are attached and you will return to your workshop item view and the pictures will be there - and perform an automatic slide show.



And as simple as that - you will have a much nicer looking entry.