In the DOpus options menu, i created a custom layout for Subversion folders with a certain column setup, that i'd like to use.
When i apply this layout to a folder it doesn't get saved, meaning, every time i open that lister again, it has it's default layout.
How can i apply my layout to my Subversion folders and the contained subfolders without having to turn it on again and again?
In the Folder Options dialog you can select Save... for this Folder which will make the settings stick for the current folder.
At the moment, to make it apply to subfolders you have to go into Preferences / Folders / Folder Options and edit the folder format at the top. On the last tab (Options) you'll see a checkbox that makes the format apply to all sub-folders.
You can also add formats for paths via Preferences directly and do everything in there without having to use the Folder Options dialog at all, which saves some steps.
If your formats still aren't working quite how you want them to, have a read of the Folder Formats FAQ which should answer all your questions. If it doesn't let me know!