Hello Joachim,
I have tried this now as well with the Wordpress installation of Sourceforge.
It works a bit clumsy, but you get it to work with the correct path including the parent page this way:
First you need to select the Parent page, spanish site.
Then you should click "edit" on the permanent link, and even if you make no change, click save on the permalink, and then click "save draft".
The permalink does change to what you expect.
I have tried this for a couple of pages, and it worked.
Regarding BlogDesk: I have enabled this in the Sourceforge Wordpress (BlogDesk FAQ: "go to Settings / Writing and activate the XML-RPC protocol").
Unfortunately, I could not get it to work. sourceforge.net/apps/wordpress/o ... xmlrpc.php shows "XML-RPC server accepts POST requests only.", so that at least works, but when I try to upload something from BlogDesk, it gives an error message.
For the moment, I think the web interface just has to do.
If you change the default view to display 100 pages in the list, and open the pages in a new tab window in your browser, you don't get lost too much, I hope.
All the best,
Timotheus
IR