Is there a way to increase the terrain size and/or make the terrain infinite in iClone 7?
This is something we have dealt with since the beginning. Yet, this isn't a bad thing either.
The Quantum Theory terrains are a very good example.https://www.reallusion.com/contentstore/featureddeveloper/profile/#!/QTE/iClone
You can place them side by side and create larger terrains, however you would normally do better with a 2d backgrounds to conserve resources.
I make still images from 3d images using my video Sony Vegas, but there are other ways.
Larger terrains might work well enough with a powerhouse computer during development, but for videos it best to alter DOF (depth of field) to take out a lot of the detail for large scenes.
We view HDTV and think the details are there... they aren't. Just would not be realistic with high definition backgrounds and high definition foregrounds.
Don't lock yourself in thinking 3d everything.