Dimmer questions

Leading edge. The difference is that trailing edge is better suited to electronic transformer loads, although the leading edge C-Bus dimmers will work fine with these up to a point..

You can run
- normal mains voltage incandescent lamps
- iron core low voltage lamp transformers
- electronic low voltage lamp transformers, subject to a limit of 300nF total capacitance per channel. This is dependent on the transformer you choose.

That's up to you.. some people might use a punch down block. I suspect most don't run them all back to node zero, but instead daisy chain them so by the time you get back to node zero you only have one or two cables to deal with.

Nick