svnhook is a subversion hook for the old editor and appbuilder.
svnhook is compatible with Progress version 9 or higher and works on both Windows and UNIX/Linux.
svnhook is based on The Progress Standard Libraries version 01.01.02 or higher.
The Zip file comes with a procedure for loading files into your repository.
I recommend TortoiseSVN with WinMerge for browsing through your repository.
Yes, the Hive has always had Subversion repository hosting. It's not obvious, but it's true.
You can see what repositories already exist by looking here: websvn.oehive.org.
It's not integrated into Drupal in any way, at least not for now. The plug-ins that we looked at for integration were rather immature and not very compelling. We'll have to find some way to make it more obvious that SVN is available on the Hive.