I had a similar question, last month - although my broody was not getting picked on my the other hens in the coop, I was concerned about the nest box being several feet off the ground (with a ramp for access).
Since my broody was a bantam, the advice I got was to make a partition with a opening small enough for the broody to get in and out, but that would exclude the big hens from the nest box. If your hen is full size, that won't work.
I ended up leaving her in the nest box, where she hatched her chick. I put food and water in the next box area for them both. Two days later I found that she and her chick had made their way safely down to the floor of the run. I'm not sure how they did it, but the chick didn't get hurt.
Only you can make the best decision for your broody, but if you think she is going to get hurt by the other hens, you might want to move her for her protection.
What didn't go well last time? Did she abandon the eggs? Was she pushed off the nest box?
For me, my main concern was that my broody might abandon the egg if I move her. She's a young hen, and it was her first time being broody.
I'm sure someone else can give you more seasoned advice, and I wish you and your broody a successful hatch.