It's been a while since I read that thread, but here's what I do when I create a brand new svn (I just tested it and it started to download, so it should still work, plus I've done this with several different mods):
Create your svn folder (it can be anywhere except your BTS\mods folder).
Right click anywhere in this folder, and choose "SVN checkout".*
Make sure the repository URL is correct, and the name of the folder below that matches where you want to download to.
Click "OK".
When finished, export the files to your mods folder. In the future, choose "update" instead of "checkout".
*be sure Tortoise is installed first, or you won't get this option