Re: your last question: I have built my own exposure unit by putting in unfiltered blacklight bulbs (BL as opposed to BLB?) Anyway, they appear frosted white when switched off, so think of tanning bed bulbs rather than college dorm room bulbs.
I'm 99% sure that as long as the bulb wattages are similar, you're not going to run into any problems. I wired together all my fixtures and they all work fine when I turn it on. I haven't yet tried printing anything with it, since I am very lazy and I am trying to figure out how far above the paper I want to put the bulbs so I don't get any lines of varying exposure.