I recently updated my dakota 20 to version 2.4.2 and found out that when I choose a track and press the GO icon parts of the track don't show up on the screen and the thick purple line disappears while I'm zooming in. Instead, I get this triangle marks along the track with an up/down curser. I can bypass this problem by enabling the "show on map" but I still want to figure out what can cause the track to disappear.
