What a great video, you do a really good job explaining things in enough detail that I was willing to tackle this job. Otherwise I think I would have just paid someone to rebuild the box.
There was one o ring that was removed from the spool valve where the worm drive sits. I don't think I saw in the video where you replaced it (I could have missed it). I did replace it so hopefully that's correct. The removal was at 44:45 in the video.
One thing I noticed while trying to assemble the spool valve back together, mine had a small dot on the bottom in line with the hole. That helped me keep things straight so everything would "click" together. I got to reinstall that assembly twice because I forgot the piece that has the bearings on my workbench. I kept wondering why the cap was so easy to spin on all the way in.