You might discuss the chart and detail with C-map but there is a ton of selections to turn on/off detail in the machine; I would recommend playing with first. They have a lot of VAD (Value Added Data) that can be turned On for additional detail on most of their chips. The Mapping chip has nothing to do with the waypoints and routes user data. Both the older GP1870F and newer GP1971F uses C-map 4D mapping. The only difference is the chip size (full SD vrs microSD) but most C-map 4D chips use the adaptor so if you had mapping before, it should have been a matter of just removing the adapter and reusing the same map. If the chart was really old and didn't use the adaptor, C-map might have offered a swap out for the same chip in micro format. Not really something for Furuno to be involved with though. That is all related to C-map and their product support. If you still have question relating to the C-map mapping I recommend contacting them. They know their product best.