Warning when trying to add .dae file

I've created a 3D scene in Poser, saved it as a .dae file and attempted to add it to an iBooks Author page as a 3D widget. When I do this, the following pop-up appears:

"This 3D file may not perform well on iPad. Consider replacing this 3D file with a version that has fewer polygons or smaller textures."

When I preview the page with the widget on it, only part of the image appears. It does rotate in 3D space.

Does anyone know a work-around so that iBooks Author will accept the .dae files that I bring in, displayed in full? Thanks!