When placing cells in files there are times when the cell library that is attached has a color table that is not the default color table or maybe even a custom color table. i.e. Cell library may have the AutoCAD color table(acadcolor.tbl) attahced. This can cause the cells to appear with different color when being placed. Ideally you want to have the same color table in the cell library as you do in your destination file. But when you don't what can you do?
Even though this settings is under reference file preferences it also controls the behavior when placing cells as well copying elements from references.
By default this preference is on so that MicroStation will preserve the RGB color of the original element and not the color index.Remapping the color indices to the closest rgb match in the destination helps keep the color as close to the original color in the cell library even though the color table.
Keeping the color index means that the same color RGB number will be ussed from the cell library. While the color value will not be matched the color number will be consistent from cell library to DGN file. This is important if all your cell placements should be done with same color number.
MicroStation V8 Cell