Everything you need to know to create a basic map is already written down here :

click me[modding.dawnofwar.com]

I will add some other stuff, probably via short videos explaining a single feature and invite others to do so as well. Ask questions in the comments, if you have stuff to share I will gladly add it.

Fixed by the devs, there is no prefab file getting generated anymore automatically!

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In case you already spent time more often editing your map and you saved it several times or exported the package several times you might encounter the problem that your map isn't shown in the game, to solve this you have to do the following:

- open up the world builder and load your map, if its opened save once more and follow

- go to "C:\Users\UserXYZ\Documents\My Games\Dawn of War III"

- open the folder modssource\scenarios\ and here is the bundle of source files which will be put together when you export the package

- delete the one belonging to the map you work with ending with .prefabdata
for example "mymission123.prefabdata"
______________________________________________________________________________
source of evil picture example:
______________________________________________________________________________

- now go back into your world builder and export the package

- now you should be able to see it ingame again

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Fixed by the devs, there is no prefab file getting generated anymore automatically!

Updating your map is basically a similar process, but we need to use some tricks here as well to go through the process just fine.

Let's begin
( I assume you have uploaded your map and subscribed to it )

- desubscribe your map, go to your C:\Users\Duderino\Documents\My Games\Dawn of War III\ folder again

- open C:\Users\Duderino\Documents\My Games\Dawn of War III\mods\scenarios\subscriptions\
and find your number ( also included in the link of your map's workshop link - the workshop ID, right click on the page, copy url and paste it somewhere to find out )
by opening them and looking for your package

- as I assume it will always copy to the C:\Users\Duderino\Documents\My Games\Dawn of War III\mods\scenarios\local\ folder as long as it's in the subscriptions folder, we delete it for now

- your overhauled map's package will probably get exported to another folder or an old folder which you used in local so you either
-> copy your .sga from that folder, put it into the WorkShopID folder from the published map in local, just overwrite the old if you are sure about it
-> or just directly overwrite the .sga over the C:\Users\Duderino\Documents\My Games\Dawn of War III\mods\scenarios\local\MapWorkshopID\levelname.sga

- go ingame and check the workshop page, you can now publish the already published map again
( which is the MapWorkShopID folder in local )
and it will overwrite its current workshop entry
!you will lose your current description!

Note that there is always one published map version after you uploaded it, this is where the changed package goes to update your map (WorkShopID folder in local ). Saying that because usually people get confused, after you uploaded you map you will probably have the map 3 times, one is the WorkShopID folder in local, one the old save folder in local, and one the WorkShopID folder in subscription if you did subscribe to your map.

Camera movement :

middle mouse - slide with the camera over the map
holding alt + mouse movement - changes camera perspective ( very important )
arrow keys to move camera without mouse

Placement :

While selected
hold c and drag the item(s) away, it/they will duplicate with the same rotation
hold H and use mouse to change height of current selected item(s) directly
press W - change in placement mode
press R - change to rotation mode
while dragging hold shift to rotate
hold H + mouse - increase/decrease height directly*

*doesn't work after you rotated an object

After some trying I figured out a good way to set the camera for maps using height level 2-3:















Ingame level 2 terrain with these settings:

I hope this is helpful to some, more is to come.

My first project as an example:

click me

If you have specific requests let me know, I will try to cover everything to come with short videos.