It looks like you're getting three sections because CC3 calculates the map in three sections (or however many sections are appropriate for its algorithm based on map size). Unfortunately, the lighting computations only work within each section. It's a limitation of the lighting filters. The limitation is that the filters assume that they have all the information that they need when it's time to compute the shadows for the lighting, but CC3 does the multiple band output then that assumption gets violated. Note that the assumption is perfectly valid for drawings without filters or for drawings with only local-area filters; it's the filters that need global information that have problems.