The NexusRip might give an error on "LibScreenParams" when separations are being ripped.
The cause is to be found in the curve used by the RIP. In the curve, you can define a tree depending on resolution, dotshape, separation, ruling, etc. The rip will depend on what's defined in the rip settings. Hence choose the correct curve depending on those parameters. It might happen that there is a parameter defined in the file that's not available in the curve, for example a spotcolor, different dotshape, unknown resolution.
The following error appears on the Rasterizer or Assembler module. This error is also visible in the control.log.
The easiest solution is to add a default curve in Symphony. This will be the curve on which the system will fall back if an undefined ink/dotshape/ruling/resolution is used.
Open a used curve in Symphony.
Select the default curve on the left.
Add the values in the column on the right and click the OptiCurve button.