Ladder and microlite questions

Can you use the microlite standoff (as in picture) to hold you off wall or will it roll down wall and you'll fall off?

With the locking off part of ladder which makes the two sections not come apart, do you fellas always lock it off so ladders cant separate when going up high?

I don’t think that stand off is fitted to the ladder properly it’s to one side it should be central to the ladder , but yes they are designed to be used like that , most ladders don’t have those locking things on them your weight up above will prevent the ladder separating the bottom shouldn’t move if it’s put up right 

Purple...the rubber D rings aren't really 'wheels' per se, or rather they don't act like wheels, rather they compress (to a 'D' shape) under the ladder/bodyweight and deform to press flat on contact with the surface. Hence, no it won't act like a wheel and roll you down the wall...anyhow if doubt, just whip out the ankalads ?  for a belt and braces.

What I would caution is the microlite can 'shift' a little bit - due to the way the brackets 'lock' on the ladder, so personally I'd prefer to terminate the ladder below the window, depending how close the tops of styles are to the pane, just in case imho.