Hi, Ira,
I can only say 3.1. 
First, I am unsure how you want to create your website. You post in Interactive Designer, which exports SWF (Flash). Then you mentuon GoLive, which exports HTML. Both formats are web formats but they are different (like a RTF file and a PDF file in print). Both have advantages and disadvantages. Of course both formats can be combined, so like a logo in print an SWF can reside in an HTML page.
QuarkXPress 8 offers two layout types to handle each (Interactive = SWF, Web = HTML).
Ira2:1) I can handle type and layout in Q blindfolded, so I would really like to create my site elements in Q , export them to the appropriate file format, and just plop them onto the HTML page. (GoLive for now, and no jokes please.)
If you want your designs and fonts to be handled correctly and display crips, then SWF is the way to go. Yes, you can just convert your print layout or start new, design it with the same feature set as in print and then export as SWF. Adding interactivity to your SWF is also possible (within the Interactive layout).
If I choose a standard RGB for the background of the home page, for example, and use the same RGB background for my exported Q elements, am I guaranteed a match?
If you don't turn on RGB color management for RGB destinations, yes. An exception might be pictures that need to be converted (thinking for example of EPS).
2) Anyone else here who sticks to the nice and comfy Q environment to develop web sites?
See here: http://forums.quark.com/t/16613.aspx
3) For an Action, and its cursor preferences, is there any way to add a customized cursor icon, something that will be available to me all the time?
Yes, kind of. First, in preferences you can choose from a range of pre-fabricated cursors. If you want to design your own, that's possible though a bit tricky (design an object, move it to mouse position, make it sticky, hide standard cursor).
Enjoy!
Matthias
Matthias Günther
Senior Product Manager
Quark Software Inc.(Please note: As I am traveling frequently, answering your post might sometimes take longer)
Want to easily publish for the iPad, using high-fidelity designs with stunning interactivity? See here: English:
http://youtu.be/Gldk5lvXXTA French:
http://youtu.be/nsgB4Q7lQzg German:
http://youtu.be/lecdenqaUGY Italian:
http://youtu.be/wjBpYZsF-8s
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