Well, the ones in the Milky Way galaxy leave us be. But recently we encountered another group of Ascended beings calling themselves the Ori and forced people to worship them due to gaining power through that worship. I'll admit, we brought the attention of the Ori to ourselves but we've been holding them at bay for now.
Naquadah is a type of metal we're still working to understand back home but it's a kind of power source. It's stable so it makes a good energy source though it can be used to amplify explosions. There's a variant of naquadah called naquadria that's extremely volatile but the energy output, when harnessed correctly, can be used for hyperspace engines.
So far as I know there aren't any Stargates here but that doesn't mean they don't exist here in some fashion. But yes, I've traveled through the Gate numerous times over the ten years we've been using it. It was a bit similar. Essentially when you travel through the Gate your cells are deconstructed and hurled through space to the connecting Gate. Travel takes only a second or two before the buffer reconstitutes you whole.
The inner ring spins allowing the top chevron (as we call it) to lock it in place. After the address is entered correctly, the wormhole is established though that's the more dangerous part of using the Gate as the energy will rush out and will destroy anything in it's path up to several feet. We also got wise when using our Gate and installed an iris over the opening that we could open and shut. It's only millimeters from the event horizon so matter can't reconstitute.
That's probably true. It's a double sided coin. Without that curiosity none of the breakthroughs made would have happened but at the same time, some probably shouldn't have been made.