Lots of questions and or/observations there. Actually most answers can be found/confirmed by searching the forum.

In essence, MS Flag needs to be 0 for BC to see an image. Change it easily with ImgTool or with GMAPTool.

Most of your other observations are basically correct but if you're suggesting literally that 'Mapsource patched ..... allows one to create many .img files so the 4GB FAT32 file limit is overcome' [my empathis], that's incorrect. As you have stated, the file size limit [actually 4Gibibyte - 1 byte] is a FAT32 limitation, and it cannot be [physically] overcome. From what you wrote elsewhere in your post you understand that, so probably what you mean is that you can create larger single images up to 4GiB by joining smaller maps from gmap folders, and yes that's right. You can also join smaller images together using GMAPTool. In either case beware of overlapping data from different FID maps. As well as the ~4000 tile limit with modern outdoor units, there is also an upper map limit of ~16 i think.

The problem is often not so much the size of the card, but the nature of the data on it. I've used both a 32GB and a 64GB [reformatted to FAT32] in some modern units and they work fine. But depending on the size of the tiles and the number of maps you'll soon run up against the other limits as you've found and long before a 32GB card is anywhere near full. 62c has 1.7GB of internal memory as well, but that isn't a great help. Numerous smaller cards with individual maps is the best policy imo but others may disagree.

[Only registered and activated users can see links. ]. [Only registered and activated users can see links. ]. [Only registered and activated users can see links. ].