both World Wind and Virtual Earth have been updated since releasing the plugin ... so i wanted to see if it still worked. ... and it doesn't. looks like v3 of VE is innocent, but v1.3.5 of WW is the culprit. particularly the TerrainAccessor implementation. saw a post in the forums that confirms that it has been touched. interface hasn't changed, but behavior has. first, it locks up when requesting terrain data from WW servers. second, the returned results aren't as reliable, and i'm getting more flat tiles without terrain data. will have to dig back into the WW code and see how i should be using it now. come to think of it ... i'm not sure i was using it correctly to begin with :)
made some changes in my original code too. fixed a bug in the Update() method to better handle the current tiles and reduce resource usage. also made a change in the Render() method to improve performance and increase fps. if i can get terrain working reliably, then i'll make a small 'point' release.