Have you removed any previous JCV files from the folder? Earlier files will interfere with the operation of the correct one teamed with the current map. Or are you saying that you expect to see the classy photoreal pics like your 3790 shows. The 42 junction views do look a little different.

Are you using the latest version of GE? Uninstall it and re-install after removing your device first. Your 42LM should be offered the 2014.20 EUU since 29th Sept.