When you tried GW, how long did you spend at each stage? For some LO's, I think you can move through the stages quicker; however, I knew DS's need to be rocked to sleep was totally our fault, and I choose a slower approach with him. My goal was to spend 1-2 weeks at each stage. However, due to circumstances such as having to go out-of-town for about a month, it took us about 3-4 months to totally move from rocking him to sleep to lying DS down in his crib after BT routine and just walking out, shutting door.
I slept on an air mattress beside DS's crib for probably WAY too long! But, if he woke up at night, I was there to help him back to sleep at whatever level we were on (i.e. pat to sleep, saying our "sleep phrase," etc.). By the time I was totally out of the room, DS's night wakings had been eliminated. So, I do not have any experience with NW's once sleeping in another room. However, if you are in another room, I would not let her CIO as this may cause her to lose some of her trust. (okay to let her cry if you are in same room and using rubbing or talking to comfort her though). So, perhaps you could go to her and rub her back, use "sleepy phrase," etc. to see if she will lie right back down.
Hopefully, someone with a little more experience in that area will come along with some more advice for you!
I do have a couple more questions for you: Do you have a key sleepy phrase that you consistently use all of the time? Does your LO have a lovey that she sleeps with?
We felt we had no choice but to move DS to a toddler bed at about 20 months because he climbed out of his crib!!! I had totally planned on leaving him in his crib for as long as I could (over 2 years old). However, once he learned to climb out, he did it consistently, and we were afraid of him injuring himself. Much to my surprise, DS did WONDERFUL with transitioning to a BBB. I thought we were in for weeks of sleepless nights and GW training all over again, but it only took him a few nights to learn to sleep in his BBB. Now, after his BT routine, he climbs right in his bed himself and lies down....sttn in his bed...and sits up in bed (but stays IN the bed) and waits for me to come in and get him in the morning! I have a baby gate right outside his door just for my peace of mind as well.
How is teething going?