Extra chores and a loss of privileges

My 14-year-old daughter earned a few chores several days ago and still has not accepted them. She has spent the last few days doing everything she can to find interesting and fun things to do without me knowing – taking really long showers and baths, sneaking books and her brother's radio, doing craft projects in her room, drawing, etc. With four younger children and my husband working long hours lately, I haven't been keeping track of what she's doing nearly often enough, and I'll admit at times I'm hesitant to check because I don't want to start another battle. She has ADHD and has major trouble with focus and motivation, but these last few days have been exceptionally bad as far as those things go. How do I/should I keep her from doing these things that she fills her time with to avoid doing the assigned chores? I feel like I shouldn't prevent her from bathing every day, but she'll spend well over an hour in the bathroom and I'll often find something in there she was playing with/reading when she comes out. Also, she's so creative that she can have fun with almost anything, and we can't hide every book and craft supply in the house. What exactly are the privileges she's not allowed to have before doing her extra chores, and what do I do when she sneaks doing things she shouldn't? Thanks for your help!