I finally figured it out and I feel like an idiot for thinking soon. You have go to the killing floor system in your files and go to the server perks with a gear on the paper. Then copy and paste the link of the skin you want on the bottom of the command and I MEAN BOTTOM. click it so there it's actually there and save it. To add more click the previous thing you added, copy and paste, then go in between the previous and the new one and press enter. Then rinse and repeat. I hope that helps anyone who having trouble with adding players skins. I had trouble with this until today. Add me if you want to play a few rounds, until next time. :)

So I did what you said. It took me a little bit because I had no idea you had to subscribe to some dude to even get the serverperks file, but I did it. Anyway, the problem I'm having now is how I even select the skin to begin with. Is it just supposed to appear on the character select thing? Also, is "CustomCharacters=TinyTina.TinyTina" the file I was supposed to put in the serverperks file?

Yes. You also have to enable a mutator, something with veteran in the name. It will set your perks to zero, but looks like it's the only way.

GOT IT. Thank you guys for your help. I'm new to the steam/KF community, so I'm glad to see that it's so responsive.

If anyone is having trouble with getting this mod to work, message me and I'll do my best to help you get it going.

Too bad I don't really see the point in using this, if the perks are not allowed to progress. This character should be made into official dlc instead of ♥♥♥♥♥♥ recolors they put out.

I completely agree now. I knew that no one would be able to see my skin, but I didn't know that you wouldn't even be able to use it on regular servers.... What's the deal with that? I suppose it's because there wouldn't be a need to by the dlc skins if you could just use your own.

I can't find ServerPerk.ini
There's ServerPerksDefault.ini