@Leda hi there, getting to this thread late but wondered how your aeoniums are doing? Mine look like "heck" during the winter when I bring them indoors...I just don't know how else to deal with them, I think they need a bit more water than other succulents - but the really cool thing is last year when I brought them back out for the summer, I cut off the tops leaving a bit of stem (these are rooted plants) and they came back within a month!!! Totally bright and lovely! Now I keep wondering "do I keep bringing them inside where they nearly die each year?" or after summer this year give mine away to someone who may be better at winter care!
Good luck (I think especially in Denver your summers are shorter so it may even be harder...if you do figure out how to water them during winter - please post it so we can all learn!