We have made an effort to provide some support for Subversion, but it is not complete yet. The GitHub version of the editor will (mostly) work out-of-the-box with both SVN and Perforce. The version of the engine downloaded through the Launcher does not come with the SVN and Perforce binaries, and will not work with SVN without a workaround (explained below). The Launcher version should work with Perforce if you already have a client installed, though you may have to manually input your workspace name.
If you want to use SVN with the Launcher version, you can work around it with the steps below. Fair warning, though: this is not an officially supported workflow, so use at
your own risk.
1) Go to http://www.visualsvn.com/downloads/ and download the Apache Subversion command line tools.
2) Open the zip file and go into the "bin" folder.
3) Open Windows Explorer to your engine installation path's ..\Engine\Binaries\ThirdParty\ folder (default would be C:\Program Files\Unreal Engine\4.0\Engine\Binaries\ThirdParty\).
4) In ThirdParty, create a folder named "svn" (no quotes).
5) In "svn", create a folder named "Win64" (also no quotes).
6) Extract all of the EXE and DLL files from the zip file's "bin" folder into "..\svn\Win64\"
7) Start up the editor and enjoy using SVN.
Again, this is not an officially supported workflow, and you may still run into issues. If you have any questions, please let us know.