Display GPX in Google Maps or other simple application?

Display GPX in Google Maps or other simple application?

I need an application that supports the following features:
offline map (no Internet connection)
bookmarks (POIs added by me from either my PC -> KML or in the app itself)
Since (Google) Maps doesn't currently support bookmarks, I use MapsWithMe
Pro which does (along with offline maps).
I now need to import a GPX trace before going on a bike trip.
MapsWithMe doesn't support GPX yet, and failed importing KML files as
converted with either GPSVisualizer or Gpx2Kml.
I then tried Locus Map Free and OsmAnd, but found them way too complicated
for my need.
So... is there a way to simply display a GPX file in Google Maps on top of
an offline map (no Internet connection available), or some other app
that's a no-brainer to use?
Thank you.