I have downloaded the US Blue Water Charts. Do these need to be unrar before unlocked? Or both? and could you explain the methodology of unlocking and placing in the correct folders please.

Please use button search, and you'll se that you'll find answers on your question, in section software you have explained unlocking maps! And when you write about some maps etc. , write where have you downloaded it, add link, then we can check what about you write!

Yes, suer, it needs to be extracted, i don't know what's inside, cause it's not my upload, but you can add here link, and i can cehck it...

The link and thread is located HERE

I have unrar'd the .rar files and have the GMAPSUPP.IMG file ready but I really don't understand the installation process for this file. Yes, I have searched and found the thread that explains the keygen and installation process but it eludes me. I think I have to rename the above file (GMAPSUPP.IMG) to GMAPSUPP.UNL and place it in the device under the .UNL file on the device, is that correct?

If so, into what file should this go? This is what my device shows for folders:



However, I would like for these maps to reside on an SD card and use them as plug and play when I need them.

No no, you are wrong, you don't have to change GMAPSUPP.IMG to gmapsupp.unl, just copy-paste that file GMAPSUPP.IMG to your device-internal memory in garmin folder, or if you want maps on SD CARD, make folder Garmin, and copy-paste inside GMAPSUPP.IMG, use keygen from section software to generate key for your maps, for MAP ID use number 411, and that generate key copy-paste in NOTEPAD document, and save that document like GMAPSUPP.UNL (select for type file - ALL, when you save GMAPSUPP.UNL). You'll need CARD ID for unlocking maps on your SD CARD, you'll see CARD ID when you put locked image in garmin folder on your sd card, and put it in you garmin device, and go to tools\settings\ about, and look there for CARD ID, that ID you'll have to put in keygen 1.5 for generating unlock key...

Just follow described procedure for unlocking maps in thread where you can find JM keygen 1.5 for unlocking maps...