Modding/Uploading your own mod to the Steam Workshop
You can upload the mod you have made to the Steam Workshop to share with others.
Make sure the mod folder contains no extra files, since the whole folder with all its content will be uploaded.
Next, to go to the MODS menu and find your mod. Rick click → Upload to Steam Workshop. This will open the upload menu.
Here you can see:
- The path to the mod folder.
- The name and the description that will be given to your mod in the Workshop.
- The preview (thumbnail) image, that will be visible on the mod page, and the one you will see on the search page.
- The visibility setting.
You can change any option except the path.
Note: any special formatting used in the description will not work on the mod page in the Workshop. Supported syntax can be found on this Steam page.
Note: you can pick the more higher resolution image as a preview image, if available. By default, the logo image from the mod folder will be used.
Once you hit Start Upload, the mod will be uploaded to the Workshop. Once complete, a page with your newly uploaded mod will open.
This also creates a
.workshop file in the mod folder. This file contains the ID of the mod in the Steam Workshop.
Uploading the updated mod is easier than publishing it for the first time.
All you have to do (after making your changes) is go to the MODS menu, find your mod, Rick click → Upload to Steam Workshop.
Note: if you deleted your mod after uploading it, this action will prompt you to upload it again instead of updating it.
To fix this, firstly, you need to place your mod folder in the mods folder. If you happen to not have a backup, you can get your mod from the Workshop and then copy it over to the mods folder.
All the mods for the Cosmoteer downloaded through the Workshop can be found in the Workshop's
contentfolder within your Steam install — usually here:
C:\Program Files (x86)\Steam\steamapps\workshop\content\799600.
799600number is the actual ID of the Cosmoteer Game on Steam. It's a little tricky to look for the specific mods within the folder, since the sub-folders are all based on Steam IDs, but you can look the URL for the mod's Steam page in order to match the ID.
Once you find your mod, simply copy it over to the mods folder.
After that, go into the folder and add a
.workshopfile. Open it with a text editor and write the Workhop ID of the mod. It's the same ID you were using to search for it the the
Once complete, the Upload to Steam Workshop button will prompt the mod update instead of a new upload.
Note: currently, the logo is not updated automatically, like everything else in your mod.
Steam Workshop, for some reason, also doesn't allow you to change the thumbnail image on the mod page.
So, the only way to do it for now is to do it manually, using a special Valve developer tool. You can read more on it below, in the Changing the thumbnail section.
This will prompt you to add a change notes. Here you can also see the path to the mod folder and a button to view the mod in the Workshop.
Once you hit Start Upload, the upload will begin. When complete, the mod page will open.
Any change notes you added will be displayed in the Change Notes section of the mod page.
Changing the thumbnail
Currently, the thumbnail of an uploaded mod cannot be changed neither through the Workshop itself nor the game (this feature is in development). We must use a special tool made by Valve to do this (based on this guide).
The first thing you must do is download SteamCMD from the Valve developer website and extract the zip file somewhere on your computer. You should see something like this once extracted:
steamcmd.exe application file, located in the extracted files. It should open a command prompt window and start downloading a bunch of files for first time setup.
Once completed, you should end up with a command line that starts with
The next step is to log into Steam using the console you have opened. Enter the following command, replacing
STEAMGUARD with your account credentials:
login USERNAME PASSWORD STEAMGUARD
Note: if you do not have Steam Guard enabled on your account, use the command without adding anything after
If everything was successful, you are now logged into the steam developer console! You should see something like this:
Now we must create a VDF file to upload to the Steam servers. This file will contain information about the mod and the image, along with a changelog message.
To do this, create a text file inside the folder where the SteamCMD has been unpacked to. The file can have any name, but must end with
.vdf extension (instead of
.txt extension that the text file was created with).
Then, open the file and copy inside the text below. Make the necessary changes based on the description below.
"publishedfileid" "Your Workshop Project's ID Number"
"previewfile" "Your Thumbnail Image File Path"
"changenote" "Added thumbnail."
appidis the Cosmoteer Steam ID and remains unchanged.
publishedfileidis the ID of your mod in the Workshop. You can get it by going onto the mod page and copying the page URL. It will look like this:wherehttps://steamcommunity.com/sharedfiles/filedetails/?id=XXXXXXXXX
XXXXXXXXXis your mod ID.
previewfileis the path to a new thumbnail image file. You can put it anywhere. If you have unpacked the SteamCMD to the desktop and put the thumbnail image in there, then the path to the thumbnail could look something like this:Or, if the thumbnail is in your mod folder, then the path to it could look like this:C:\Users\<username>\Desktop\steamcmd\image.pngC:\Users\<username>\Saved Games\Cosmoteer\<SteamID>\Mods\<mod name>\logo.png
changenotecontains the change note that will appear in the Change Notes section of the mod page, once the thumbnail is uploaded.
Once you have done editing, save the file and go to the SteamCMD console. Then, type this command, replacing
FILENAME with the filename you have chosen previously:
This will start the upload, replacing the mod's Workshop thumbnail image with the image you specified earlier.
Note: uploading an image larger than 500 KB might result in the rate limit exceeded error.
If encountered, try to reduce the image size by shrinking it or compressing, until its size becomes less than 500 KB.
After the upload, it could take a minute to actually update the mod thumbnail, so be patient. SteamCMD can be closed with the command below (recommended) or by just closing it.