Click and drag to rotate the model. Let go of the mouse to render it. Press space to toggle Rendering Mode. If the program detects that your PC is too slow to handle realtime mode (ie. the render breaks) at the current Resolution, it will switch it off. If you want to re-enable it, increase the Poly Resolution first. Realtime Cube: http://scratch.mit.edu/projects/10536676/ To Import your own model: Export the model as a .obj file (make sure all faces are triangulated) from a 3d modelling program like Blender. Click "See Inside" on this project, click "import model" then right click the "OBJ" list that appears. On the context menu, select "import" and choose your obj file. Click the "import model" button again to read the file. To import your own texture, first convert it at: http://dl.dropbox.com/u/12239448/ScratchTexture/index.html Then do the same as above, but instead on the "Textures" list and instead importing a .txt file containing the output of the converter. Press "D" and type in the width and height of the texture as asked.
I give all the credit to DCPU-16 for making the code; I just imported the Yoshi Model. Credit to Nintendo for making the model, and credit to Alec Pike (http://www.models-resource.com/) for ripping the model and the texture to go with it.