Yes, the grid is included.

Of course, it's the same frame

It fits on the Amaran 200x, which I think is identical in construction...

The difference lies in the construction of the softbox. If you often transport and set up the box, the Light Dome II is more convenient because the struts can be easily folded out and back in again. With the Light Dome SE, the struts have to be plugged in, which is more tedious. Of course, this also comes at a price. So if the box is in a studio and doesn't always need to be folded up, then the SE should fit the bill.

You might find an appropriate part at Manfrotto Sativtaschen. The quality of the Manfrotto bags is good.

Looks like Bowens. Profoto studio flashes have their own connector. So not compatible.

Yes

No, it's only to diffuse the light. The light that you get separately have to have a matching attachment.

Yes, this is the successor :-)

It needs a bowens mount. When you don't have it, you should use an adapter.

Yes it is:-)