I tried using movable light on the direction light which is the sun in my scene, then use ray trace on all other lighting, since ray tracing runs more on the GPU. Using 4.5 is unstable for me, I don’t like using lightmass because building light every time I change something is very slow, at times it freezes up my system. And is annoying building light for an hour just to preview a rendering output to just little change and less geometries.
I see the title of your issue, but in your description you are not providing much detail as to the problem you are experiencing. Using Ray Tracing does not eliminate the need to use a lightmass it only reduces the amount of lightmaps needed because you are not using static lighting.
Here is some helpful documentation on how Ray Tracing works at a more in depth level.
Here is also another user who was having trouble with his lights and shading where I provided some example of how ray tracing works in general.
I hope this helps you with your issue.