Hi Ken
In your screen shot, I see two things that you should change:
1) Instead of using the VST version of the K5 plugin, Mac users are encouraged to use the AU (Audio Units) version of the plugin.
2) For all instances of VDL/K5, you'll need to use the "VDL SoundSet 7.0a" sound set instead of "Virtual Drumline 2.5".
Make those adjustments first, and if that doesn't solve the playback, then go ahead and try things in stand alone. I'm not sure where they're located, but you should be able to launch both Aria Player and Kontakt Player from their respective install directories, or from an "installed programs" list, or whatever.
Hugh