Hi Orux,
just tried OruxMaps6.5.0rc2 ... and found some strange behaviour :? .. or understood some things wrong. ;)
Within the geocache page I can't choose "mark all; discard all; turn opposite". Within the waypoint page that works fine.
Then I loaded a gpx-export (geocaches) within the waypoint menu.
Changed the symbol of the loaded "geocaches" to -> geocache ... but now I can see 2 waypoints at the map at the same point.
One with the normal waypoint symbol ... the other with the geocache symbol.
Within the waypoint page there is only one item.