first, make sure that your track connects. its not enough to put one vertex over another, you have to use the connect option (available under edit or right click on a vertex) afterwards, a stoplight will become enabled. hit it. that will start the ride. to ride in 1st person either hit the 3d picture in picture and the ride on coaster buttons, or switch to the 3d view and, again, hit the ride on coaster button.
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Jay and Silent Bob have left the building ~Jay and Silent Bob Strike Back