Hey Meghan,
I can only answer a couple of these as I am fairly new to the Heidelberg myself. I have not used it for foiling, however I do believe the foil attachment can be added and removed for standard printing. I have used it for die cutting and scoring, which is really easy to set up. You just put the die or the scoring metal (not technical term) in a chase secured with furniture. It’s the same way you would put a boxcar in for printing. There are a few other adjustments you need to make, but it is simple.
For maintenance I love it! There are green, yellow and red dots all over the machine telling you where to oil and how often. There are metal plates all over the machine with instructions and tips on how to use or make adjustments. It’s a very fine piece of German engineering. I haven’t done long term maintenance yet. I do hear it’s pretty messy, but I don’t think it needs to be done that often.
I took a class in San Mateo, CA with Amber from Flywheel Press. She is the only person I know of who teaches on a Heidelberg. It was 3 8-hour days and I felt I learned a lot. I was still a little intimidated to use the press, but after a few runs I became confident. You really learn a lot as you use it. I’ve certainly made mistakes. It’s part of the process.
Hicks Brothers is a great resource for buying equipment (they ship) and for asking questions about the foiling. Those guys know everything. http://www.printingequip.com
Another place that’s great for getting answers is http://www.briarpress.org.
Good luck!
Jamie