Videos or pictures would help.
As far as I've tried thus far, Exporting the character from CC3 to UE4 with LODs making sure you set the correct params on import as shown in the following video grats a proper import of the character actor with LOD and morphs imported. If you lose facial animations one thing to look for in UE4 is to make sure that your character has morph sliders after the import. If not then your facial animaitons will not import as the animation exported use morph sliders for animation expressions. https://www.youtube.com/watch?v=hyfKQyXvTAc
Secondly, when exporting animations from IClone, CC3 or 3DXChange make sure that morphs are exported with the animatons. If they are gone then they will not appear in UE4. For my work flow as of current I make an animation libraries per actor and save them with motion plus via collection into the motions plus custom folder. Because rook motion does not work in iclone my game play animations are in place.
As for sequencer and animation scenes where i need charters to move around the scene and operate I use set markers to mark the starting place of actors and make the iclone animation for the full scene. The root of the cutscene actors will not move from the starting marker because the root bone does not move.
Note my experience is from a few months back when i was experimenting with CC3 and Ue4 operations.
Note the cut-scene at 12:00