As said before use Homeport for Marine charts (Bluecharts etc) and Basecamp for all the other land maps.
Basecamp can't read Marine charts. Homeport can read land maps but only as a reference to show you what is there after you get your feet on land.
Unlock all your .img files with [Only registered and activated users can see links. ] and remove all .unl files from your 60csx.
No need for unl codes and Keygen (...ancient history), that's what I've been doing with my 60csx for a long time now.
I unlock every .img before I copy it on the 60csx, and before I make a mapset of maps with Gmaptool (60csx can read only one gmapsupp.img file that can contain a full map, partial map or mapset).
I don't send mapsets from Mapsource to 60csx anymore (i.e. a combination of 3 partial maps), I send each map as gmapsupp.img, copy them back to PC, unlock each .img and make a mapset of them using Gmaptool.