Thanks for the vid! You are on the right track! Now...I'll give you another tip you might enjoy.....deep litter in the run!
Start a deep litter in there to eliminate the barren, hard packed soil and the slimy, muddiness that comes with the rain on a barren run. You'll be glad you did and the chooks will too. It's a big run so just start adding any ol' yard debris like weed cuttings, sawdust/shavings, leaves, leaves, leaves, twigs, pine needles, lawn clippings, straw, etc. Keep adding until they have 6-8 in of carbonaceous material underfoot at all times. You can't go wrong with it...it will grow the beneficial bacteria that your birds need underfoot and the predatory bugs that will prey on lice and mite larvae will find a home there. It will also give your birds something to do every day, moving that bedding from one end of the run to another.
It will smell nicer, be healthier and will make your birds happier in a more natural environment of forest floor type footing underground.
PS: I'm so tickled you are reading through this thread and mining out the good info to be found there....shows a dedication to learning about your animals and I commend you for it! Not many take the time to really learn and love the learning like you seem to do. Blessings upon you, girl!