[Jon Thorn]

Have you looke at the View pulldown menu yet in FCP? View>External Video>All frames?
Tried Refresh A/V Devices?
Tried checking whether the Video Output is the Kona card? Final Cut Pro>Audio/Video Settings>A/V Devices… is the correct Kona setting selected for Playback Output, Video?

Check these items out since you can see test patterns outside of Final Cut Pro.

Hope it helps.

[Jon Thorn]

Another AJA freeware called KonaTV will playback Animation codec clips if you select RGBA for playback in the Display pulldown menu of that application.