Baby will go down for naps, but not for the night

I recently invested in a Merlin Sleep Sack and we're now on day 4 of consistently using it. We had been using the nested bean zen sack, and it worked for about a week before it basically became an over priced sleep sack. My baby is used to either being held for naps or only taking 20 minute naps during the day and sleeping most of the night in bed with me and my husband. I think we're on the tail end of the 4 month sleep regression because naps have been getting better, just not night sleep. Today she took 3 30+ minute naps and 1 1.5 hour nap. She even put herself to sleep for one of those naps. So I'm thinking this sleep suit is working. But now she doesn't want to go down for the night. The past 3 nights I've had to nurse and rock her on and off for over an hour before she'll go to sleep. I'll attempt to lay her down several times and she wakes up almost immediately. I'm working on transitioning to a crib because I really want my bed back. Today she's taken all of her naps in the crib and has done really well. Any tips for helping her get to sleep faster? We have a consistent bedtime routine of nurse, solid food, bath, lotion, nurse, and rock. We use a sound machine and the room is completely dark.

Am I maybe changing a lot at once and she still needs more time to adjust? If she wakes up crying I immediately go get her at night and she's been sleeping about half the night in the crib and then around midnight I put her in bed with me, usually because by then she's almost inconsolable. I'm really trying to ease into this. CIO and Ferber just don't work for us. I want her to know I'll always be there is she needs me.