DD climb in and out of her crib this past weekend just fine (no thud). This morning she climb out again with a thud! Apparently she leaned over the side (I saw her leaning over the side after I put her back in because, she wasn't quite ready to join us.)
Yes we have the crib at the lowest setting. We will be transitioning her to a big girl bed in the next couple week.
Re: Should I leave the drop side on the crib down?
For the period of time when our DD was able to get out of her crib and when she got her big girl bed, we left the drop-down side down. It seemed to work because when she did decide to try crawling out, it prevented a bigger fall. The novelty of her getting out seemed to wear off after a few days so maybe that is what will happen for your DD too!
Sarah