Hi Spuggyhawk, i'm not sure if the features i am using is only in the paid version.. but I can do it by: opening Maverick (v2.5)..
open the main menu,
select "Waypoints"
select "add manually"
along the top row select "OSGB"
type the full grid ref in the "Zone/grid ref" box
then save the waypoint (save button at bottom of form)
go into the "Waypoints - collections", and select the collection you have just saved to,
then "waypoints-browse", select your waypoint, and "go to" at the bottom of that page
This gives you the navigation direction, or you can use the compass
Press the top right "to: waypoint" and choose "stop navigation" to stop the navigation.
I agree, it isn't simple, but works well.
Or, if you recognise the destination on the OS map, you can move the little cross in the middle of the screen to your destination, and hit the green waypoint symbol, and "go to".
The more I dabble with maverick, the better it gets!
Hope this is useful, if not, at least I learned a couple of things typing this out!
Peter