Open 0xr.space on the Quest, open a model and put your hands in view. Pinch once to select. Pinch and keep still for about half a second to take hold, then carry the model to a floor, table or wall and let go. Pinch twice to pull its parts apart. Pinch with both hands to scale and turn it. Pinch and swipe sideways to spin it. The same list is in the headset under More, then Gesture Help.
A select has to be a quick pinch: one held longer becomes a hold instead. A double pinch needs both pinches within about 0.7 seconds, and a swipe needs 5 cm of sideways travel within 0.7 seconds. Circle-select, drawing a closed loop round parts, works only while Explode is on. Gesture Help is not shown on a phone or a computer, which have no pinches.
It was probably held too long, which reads as the start of a hold. Pinch and let go quickly.
It folds into a small handle after 10 seconds untouched. Point at the handle or look at it to bring it back, or press the pin, Keep dock open, to stop it folding.
No. Quest controllers work too: the trigger does what a pinch does.
Yes. Pinch and swipe sideways, or turn on Auto-rotate under More for a slow, steady turn.