Jon_Saddington:
none work after export
What exactly does that mean? I assume you are using some player. It helps to state what you are actually doing. Try playing the exported video in Shotcut.
Your export failed for one or more reasons. There is always a reason why it failed. Below are the posts by others describing their faults and solutions. This tutorial is not a definite tutorial as you may have a unique situation not described in here.