[Removed due to odd double posting incident]

Hosting environments range from zshare.net, to dropbox.com. I recommend the former, although it's entries get wiped after a few months or so.

 

Here is a great list of the other major filesharing services:

 

http://lifehacker.com/388284/best-online-file-sharing-services

 

Find one that will let your upload entire folders, and that doesn't compress them into zip archives. (Techie speak for: Find one that doesn't mess with your files)

 

Then, upload the folder enclusing the UTW file, assuming that the UTW file is not a plain block world, and that the folder has no more than 3 files in it.

 

The file hosting service should give you a usable link to your uploaded files, which you can use on mars with slight, or no modification.

 

Drop me a PM if you have any questions, or if I went nuts with saying things in over complicated ways. ;) (Programmers alike have REALLY bad habits of overcomplicating explanations! I mean, I'm doing it right now in this explanation! I just now extended the complication. And again! And!! You get the picture. Again!!)