1) I understand why, as a beginner, you want to follow exact instructions. But honestly mead is not about dates/weeks. You don't rack to secondary until it's close to its final gravity, no matter how long it's been in primary. You will
not get any off-flavors from leaving it in there another month or two
It sounds like it's being a bit slow. You're not keeping it too cold are you? Did you pitch enough yeast? Did you include any nutrients or fruit?
2) Mead takes so long it doesn't normally need degassing, but you'd do this once it's finished fermenting and the gravity's not changing.
3) Add 'sabilizer', or more exactly, sorbate and metabisulphate and leave for a few days.
4) After stabilizing add some more honey until the gravity/sweetness is where you want it. After a few days check the gravity's not changing to know that the yeast hasn't sprung back to life. Alternatively you can add artificial sweetner, which doesn't need you to stabilize.
Note that adding more honey may introduce some haze to the mead again which you'll have to wait another few months for it to clear again.