i am using Reel Smart Motion Blur in After Effects with a Motion Vector Pass from Cinema 4D (rendered as 16bit PSD).
My Problem is, that the direction of the Motion Blur does not correspond with the direction of the movement.
Also the edges are sharp and jagged.
We have used this workflow before, and seemed to work.
1) Assuming your Motion Vectors are 16 or 32bpc, you might need to turn off the color management -- in Interpret Footage second tab turn it off for that layer otherwise it will remap the values (hence a potential wrong direction as you explain)