Using a timeline to move an object is easy enough. And moving it along three axes at the proper speed is relatively simple. Not so much with rotation. The problem is that I need the orientation of the actor in the map to remain as I have it set up. I thought this would be easily managed by rotating it by just using a tick event to add a finite amount to the yaw from within the actor blueprint, but add actor rotation refuses to accept decimal values below 0.1.
The alternative, using the timeline to get smooth movement, creates its own problem. The rotation from the timeline when fed into the rotate node, resets the rotation of the actor to 0,0,0. I need the actor to spin slowly, along an axis that is not perpendicular to X Y or Z.