3D model -> DICOM/nii conversion

Could you explain what do you mean by “visualization preset”? Usually we talk about presets when we are using volume rendering (directly from volume), not surface rendering (from segmentation), as we discussed in the other thread. Have you tried converting your .ply file to .stl and opening it in Slicer? Can you provide screenshots of the “noise” or files so we can try to replicate the issue?