I've looked a bit into the user manual to see if I could help documenting.
I feel the structure is a bit hard to follow now and would need a (careful) rework.
First the reference guide is divided into versions. Right now everything is documented under 0.7.4 which means it's already old.
I think we need to move everything out of a version structure. If it's possible to add tags or similar we could mark each document with the version it's written for. When a new version of Kdenlive is released we can then go through the documentation and either confirm or update the documentation and update the tag to the new version number.
Next I can't find any glossary or index making it hard to find content and use the manual for quick reference.
Is it possible to mark content into categories and groups? Is it possible to have group pages like in wiki pages? - All content marked with a certain category is listed on a category page?
I've browsed a bit more, trying to add content and I must say I think the site software is a blunt tool for documentation. I started to add Menu items and for each and every item with subitems you have to add a new page. Tedious work.
Why was the documentation moved from a wiki into Drupal? Any other reason than to have everything collected in the same site I mean? Would it be possible to integrate a wiki site into the current Drupal site for documentation?