2008/2009 Keystone Everest 340i Info?

[RVist]

Hope to hear from Everest Owners. My DW and I bought "up" from a 2003 Keystone Cougar 31' 5th Wheel to the 2009 Keystone Everest 37' Quad Slide. The unit is in Very Good condition. Apparently No Kids, No Pets, No Smokers, Well Maintained. We received most of the manuals and documentation on the unit and appliances, but lack some information. Specially,
1. The Monitor Panel shows a Black Tank and TWO Grey Water Tanks. There are only 2 Pull Handles in the "wet bay", one labeled Black and the other Grey.
I've looked underneath and around but can't find another Drain Valve for the Galley? Tank. Does the one "Grey" Handle operate BOTH Drain Valves for the Shower and Galley simultaneously, or have I missed something?
2. The slides are hydraulic (new to me), and though I can identify the hydraulic valve system with the four valves, I have no idea whether to push, pull, twist, or turn anything to select or deselect an individual valve. Any info is appreciated.
3. Back in the Wet Bay. A "Pointer" switch labeled Winterize, another labeled Water Heater Bypass. My choices for each are "on" and "off". Hmmmmm, leaves you guessing. I suppose trial and error is one option, although I prefer to learn from someone who has been there.

Thanks in advance,

[routemaster]

My kitchen valve is behind the rear wheel.

[RVist]

Thanks for the Reply. I must have missed something, and will certainly crawl back under when I go back up to the campground in the next couple weeks. I was able to see where the 1 1/2 inch drain line came out from under the kitchen and ran the 8-10 feet down to the sewer connection, but could not see a valve body, cable, or or pull handle for a waste valve. I'm certain that I'm not alone in wishing I could find a schematic of the plumbing for my model. My '03 Cougar didn't have the enclosed underside making it apparent where everything was. BTW, my '03 had the Galley Valve located behind the rear wheel. I constructed an extended handle from PVC to operate the valve when the slide was out.
Once again, thanks for your reply.