Oh no problem, I can give you all the info you need; you're talking to a forum veteran here!
Well that's a relief; I'm glad that I "got the power" - pun intended!
Yes to all your questions in your second point: the drive is USB 3.0 compatible, the cable can be removed, although only a USB 3.0 connector can be used to attach to the drive's port, and I'm using the cable that came with it, which is of course also 3.0. For more info, here's the link to my exact model, 3TB size: My Book Essential
Sadly, my only other computer is a laptop, so it wouldn't work, or I would certainly test it!
You know, I can't answer that last question, since I haven't tried plugging any USB 2.0 devices into the fussy card, and the only 3.0 gadget I have is the WD.
I can find out more tomorrow when I get home, as I can try the card with a 2.0 device and see what happens!
Thanks again for your time and patience in helping me solve this matter.