Hi Jeff
thanks for the additional files, great help to reproduce the issue.
I don't have a full explanation yet, but hopefully a workaround for you.
0. from the data you provided
1. open the (empty) cej.
2. import the raster
3. select terrain layer, fire up the 3ws exporter, open the Misc options tab:
in the global offset field, I see the infinity values (see img)
4. get rid of those by clicking center. this will reevaluate the offset coordinates correctly
5. export -> 3ws loads fine
###
I did encounter a follow up issue however on the resulting web scene: when I export the terrain on its own, I see strange holes in the resulting Web Scene. I could avoid this by adding a single shape that I manually created below the terrain (just roughly in that area). When exporting the terrain with the shape in the scene, the exported terrain looks fine (even if the shape is not included in the web scene).
It looks like there is some flaw in calculating the bounding box of this terrain, causing a) the inf offset error and b) incorrectly merged (dropped) faces on export due to precision issues originating from this incorrect bounding box.
and some good news:
I tested the same thing in soon-to-be-released CityEngine 2013, and it works fine with none of the above issues.
best
Andreas