A couple of things, the first one being the likely main issue:
1) Element is not meant to be added directly on the text layer. Instead create a new solid that is the size of the comp, add Element to it, select the text layer as custom text layer in Element Effect Controls, and only then enter Element Scene Setup and extrude the text.
2) It is probably better to create the plane from the Create button at the top of Element interface. You can create basic primitives from there. I don’t have the plane model which came with Element V1 so I couldn’t check if that had anything to do with the issue, but the created Plane Model worked just fine.
The text layer in your sample file was huge, probably because you had to enlarge it to cover the comp. No need for that doing it as per step (1) above.