I had originally replaced an unlocked "gmapprom.img" file, along with placing .jcv file in the ./Garmin/jcv/ folder and gmap3d.img in the ./Garmin folder. However, I did not replace the gmapbmap.img. After c550 rebooted, it recognized the map and works with the recently found, favorite, and places of interest (Food, Bank, Auto services etc.) addresses. But strangely, I can't enter an address on my own. When I tried, it asked me to spell the state, which I did, but showed that it was not found. I tried entering other states (US) as well, without avail. So, I can't go ahead in the menu to enter full address. The same problem I face with the jcv (intersection). Now I am left with only option of finding a route by using browsing map where I have to select a point near I intend to go. Once a point is selected, GPS works fine... Here, may be it is worth mentioning that I have used an already unlocked map and not unlocked it myself using Mapsource.
Now, I replaced gmapbmap.img file (originally was just 5.8 MB as against new one around 50 MB) in addition to the above said configuration. It does make a difference in the way it recognizes Traffic. Now, in the setting it appears that I can choose either auto or available FM bands (e.g., 97.1 or 98.3 etc) after running search. In practice, when a search ends, I see four different frequencies that shall provide traffic updates in my area. When I force selection, other than 97.1 FM, nothing else get selected. However, this selection happens on auto mode also. I can see TMC light turn green when 97.1 is selected. But, it does not work. It does not give me any updates. I tried this with the "traffic" checked and unchecked in avoidance menu while travelling to work with turn by turn GPS (I use WAAS for better accuracy) enabled. I traveled on Expressway in order to give the traffic update a full chance. Under the subscription, it shows TTN (US, Can) as well as Navteq (US, Can) Lifetime subs. I have additionally entered the codes for Canada separately for both services and received notifications of successful subscriptions. However, I don't see any entry for the same. I had a "New subscription" before that had appeared after trying a code generated by the keygen version 1.5 by JM without checksum fix. But later on, I could probably remove it successfully by entering a code generated by supplying VenID 0 as suggested on this thread. I have tried 1527 for the code generation as suggested in the posting #10 and it notifies that the code was applied successfully. But nothing changes in the subscription list. I am using:
Garmin Streetpilot C550
Software Version: 6.70
Audio Version: 2.20
GTM Software Version: 5.50
GPS Software Version: 3.00
Bluetooth Software Version: 3.40