Please do not reupload anyone's levels. It's just not cool.

Go to your documents folder, to My games, Distance, Levels, WorkshopLevels. In here there will be a couple of folders, depending on the levels you downloaded. The names of the folders exist out of numbers only, they resemble a certain Steam user. Just check them all until you find the right level. In the folder there will be two files per map, more then two means you have multiple maps of the same creator. Copy the .bytes and the .bytes.png file over to
Documents\My Games\Distance\Levels\MyLevels. Now restart Distance, and you can edit your favorite map!
The image used for this guide is from the map 'BENTCITY'.