I was working on a scene that had two spotlights in it...........simple enough. I played with the lighting and decided I would go with something different. I tried to delete the second spotlight.............Terragen crashes. OK, I says to myself, it happens from time to time. Restarted.............tried again to delete the second spotlight and TG crashes again. Restarted................I just disabled the second spotlight. I know most people don't use one spotlight, much less two. Just thought I would let you know. :)
I just tested this, but I can delete the nodes without any problem. So I don't know what causes it. Perhaps the preview is busy, then you delete and that makes TG crash. I do have have crashes when changing something (even moving the pen, or typing in another value) when the preview is busy.
I can't replicate the issue here either. Try pausing the 3D preview before you delete the Spotlight and see if it happens again.
- Oshyan