@gpshack2
Giomen is right. The thread was side-tracked into a discussion on 2nd release 200W & on firmware upgrades to support greater than 2GiB card maps. All your problems were solved by about Giomen's post at #5 but the answers are somewhat "peppered" thru the preceeding posts and some info was wrong and/or confusing. By way of apology to you for my part in the side-tracking, here it is distilled down to what you need to know.
This is based on the understanding that you have a 1st release 200W with an internal 1GB memory, and that the firmware has been upgraded. You have a 4GB sd card. Right so far? These are your options:-
Maps on the device: You may have the basemap and up to 4 detail maps on your internal memory, there are:
gmapbmap.img (basemap)
gmapprom.img (detail map)
gmapprom1.img (detail map)
gmapsupp.img (detail map)
gmapoem.img (detail map - naming may not work with all maps, not de-selectable even if it does appear in map info)

The above is no immediate help to you because your problem is that the NA & landownership maps take up more than 1GB each when together with the basemap etc so neither detail map will fit on the internal memory, therefore they must go on the SD card.

Only one image can go on the card. You must combine your maps to one image, name it gmapsupp.img.
The SD card can be any size 4GB or more, but the FAT32 format limitation means that the gmapsupp.img file cannot be greater than 4GiB minus 1byte regardless (4,294,967,295 bytes).

There you have it. If you had worked it out already, good, then maybe this might just make it easier for someone else looking for the same answer.