You need to archive your files in a gro file (which is basically a zip file renamed), with the exact same file and folder structure the game uses. (So for instance, when you open any gro file, you see that things are located in Content/SeriousSam3/ and then appropriate folders.)

Then in the editor, you can publish your gro file.

Alternatively, read this: http://www.serioussam.com/wiki/index.php?title=SED3/Steam_Workshop

Right, I am at a total loss as to how to even make .gro files. Opening all the files I need and trying to save them to a .gro file doesn't really work. Multi-selecting them with Ctrl+Left Mouse Button and then trying to save them to a .gro file doesn't really work either... It just saves one gro file with only one of the .ep files in it and I can't seem to open or move or manipulate the created .gro file in any way on top of that.

Alright, basically, I have a bunch of weapon tweaks in .ep files and I would like to make these changes available in the Workshop. How can I do that specifically?

Thanks for the help.

Umm, again. Put your files in a zip file, which is a popular archive format, I'm sure you met them if you're using a PC. Then rename the zip file to a gro file and it -should- work. You do this outside of the editor. And you can open gro files too like zip files.

For example, I use Total Commander instead of Windows Explorer to as a file browser. I only need to hit enter on gro files to open them like if they were a folder and I can just copy files there.

Oh, nevermind. I figured it all out now. Thanks once more for the help.

Basically, it all comes down to the fact that I didn't know .gro files were just disguised zip files with a specific file structure and that I didn't know the actual file path to my custom .ep files.

Anyway. It's all done and shipped out! Here's the link if anyone's interested: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=303051420&searchtext=