I've got something of a reputation here for dark roasting everything, but I'll make an exception for you
The Alpenrost will produce a lot of smoke, so make sure you've got good ventilation. Some people roast outside, I roast with the back door open and a fan running to try and reduce the amount of smoke that gets into the house (I use a Hottop).
I really would recommend you keep a detailed log of everything you roast and how you liked the results so you can repeat them and experiment based on known results. I note the weight of the batch before and after roasting, the times first and second crack started and peaked and what settings I used. That lets you taste the results and make the next batch darker or lighter to suit your taste.
Don't be afraid to experiment, try something different to how you normally roast things. I like dark roasts, and occasionally try roasting something much lighter than normal. The beauty of home roasting is that you can do that kind of thing - sometimes they work very well and sometimes you put the whole batch in the bin and try something else. Green beans aren't hugely expensive so give things a try.
If you're feeling really brave write up some cupping notes when you drink the results of your roasts, and send them to Phil so we can all see what you've roasted and how it tasted.
I wish I were what I was when I wished I were what I am.