Anyone else suffering through this kind of transition or has done it already? Anyone have any tips?

About 2 weeks ago my son figured out how to climb out of his crib. Since then we've gotten him a toddler bed. I guess I've made progress sleep training him to the big boy bed because I established a good night time routine and I've gotten him to fall asleep in it. I guess the problem is after a few hours he'll wake up, get out of bed, stand at the baby gate and cry. Let's just say he's been holding me hostage because I've been having to sleep on his floor to keep him sleeping in bed all night. Hes super clingy and stubborn. Just not sure how to get him used to sleeping in his big bed without me in his room. He slept in his crib with the door closed just fine. Now the door stays open until I go to sleep in there. Please help.