OK, so I hope I can be helpful. I have had my first for about a month and a half, but I have done soooooooo much reading to try to learn as much as I can, in the interest of a happy, healthy snake.
1) I didn't see mine drink until like a month in. They seem to do it right after dark when they're most active. Keep an eye out for signs of dehydration, but he will probably be fine.
2) It took me awhile to accept that mine would be where she wanted when she wanted. As long as it isn't too warm and an under tank heater isn't touching him (burns possible) tis ok.
3) RI can result from too much humidity. And if the bedding is too damp too much scale rot can occur.
4) This is a topic I researched alot. I too was concerned. I found that it really depends on the snake. Mine goes around once every week to week an a half. It probably took her 2 weeks or so after I got her. If it goes too much longer than that, be concerned.
5) I tend to assume exploring
6) Mine does it every so often. As long as it isn't too frequent or produces noise. And it gives you a chance to see inside their mouths! Which I think is neat, and it lets you check for RI easier.
7) See above.
To your friend: That kind of peeing or pooing when they are handled is a sign of pretty bad stress. I know its hard but depending on the snakes shyness level, they should be left alone in their enclosures (no handling unless to spot clean or refill water {daily!!!}) for anywhere from a few days to a week or so to allow them to adjust and de-stress after you acquire them.