first we find campaign that we want to port

then insert copied link to steam workshop downloader
and click on that link you get

now follow those steps on image

Easier Steps
1.Open VPK with GFCScape
2.Then Extract Files To Your Folder
3. You Done
Now you got the folder with materials and models etc.
we just gotta upload
and if you get this error just delete file it says

and then name it, select types and preview image

you done! (hear me out i tried reupload it 3 frickin times cause of 15 code)