Number of vertices
The core CHAI3D library only implement segment to triangle collision detection and not triangle to triangle collision detection.
If you need to detect collisions between objects and want to model dynamic behaviors, then you may want to consider using the ODE dynamics engine module.
We are currently working on an implementation that will use the more recent BULLET simulation framework and which will provide collision detection among objects. The release is scheduled later in April.
Don't hesitate to create new threads on this forum as these answers are often read by other developers who have similar questions. We appreciate questions like these as they help us refine the documentation and also prioritize the developments of new features.