Certain animations start out floating during transitions in animation blueprint

I’m rather new to importing animated assets so I’m not sure what I am doing wrong here. My apologies if this question has been answered before–I couldn’t seem to find anything definitive during my forum search.

I found a free rigged/animated skeleton character and proceeded to import it into my project (see link at bottom). Because all the animations were in one large file, I imported each animation into UE4 individually by specifying the frame range of each animation. Everything seemed to be working fine until I tried transitioning between various animations in the animation blueprint.

For example, the transition between the Stand Up animation to the Idle animation shows the skeleton floating for the first half of the Stand Up animation.
Watch this video to see my problem:

Anyone encounter this and know how to resolve it? Thanks in advance for any assistance.