It’s working for me when I built the engine from the Early Access branch.
One issue I have is I set up my character’s arms but there really seems to be no way to control elbows easily. If my character reaches behind, the arms start contorting and interpenetrating in a way that’s obviously not how an arm bends. There might be a way with limits but it’s not obvious how to set up limits when the upper arm bone isn’t aligned with the clavicle like a knee and upper leg joint would be.
I had some automatic pole vector computing myself for UE4 and all the standard IK nodes and it worked pretty well for arbitrarily positioned arms by basing the final pole vector off the initial chain orientation. This way, however the elbows and knees were positioned in the original animation pre IK would help influence the final elbow orientations automatically without having to specify an IK target.