This video demonstrates how fix wiring errors that are the result of a shortage of pre-assigned rails. Depending on the firing system, "rail" is synonymous with "module". Wiring errors can occur when using pre-assigned rails (i.e., pre-assigned modules) if not enough rails are assigned to accommodate the number of effects. For example, if a position has only one pre-assigned rail with 32 pins, and the position has 35 items at different event times, then 3 items will be left over after addressing and will display "error" in the Rail and Pin columns of the Script window.