glider r gravy IS critter love hpw repackaged for pp. So no you don't have to add more to it. The complete has everything needed in it except the water.
The only difference i'm aware of is the packaging and possibly the price, I've never bought anything from pp so I don't know if there is a diff or not.
There are salads that are fed with hpw original and complete on the critter love website.
https://www.critterlove.com/salad-mixtures
At the bottom there is a calculator to figure out how much you make for how many gliders for how many days. it's a little tricky to figure out at first but play with the settings on the calculator and it starts making more sense. Once you get it figured out, you can pretty much make a grocery list from it and know how much you need of each ingredient.
A lot of stuff you can get frozen to save some prep work, some of it will need prepped by hand. hope this helps some, i just started this diet and i'm not all that familiar with it as I am some of the others