The gmap versions (Mac OSX / Windows) of the OFM Benelux full version and Germany (+Benelux) contain elevation and shaded relief (DEM data).

Note for Windows users: you only need to unpack/copy the gmap folder in the default Garmin directory. No installation needed, but make sure you have de-installed the previous version.

This default Garmin directory is a hidden system folder on the C-drive (C:\ProgramData\GARMIN\Maps or C:\Users\{user}\AppData\Roaming\GARMIN\Maps). You can place the maps on another location or drive, just make a shortcut from this directory and move the shortcut to the default Garmin directory. An easier way to install those maps is with Javawa GMTK.