Next Steps
Copying one video file to another is no great feat, so we now do
something a bit more useful. Right click the mouse somewhere in
the middle of the screen and choose Transform/Timeline/Reverse.
An oval
Transform Glyph will appear. Connect its output to the Output
File Glyph. Note that the output will only accept one input, so
the existing flow is disconnected. Connect the output flow from
the input file to the Transform glyph. I have changed the flow
names (right click on the flow name to change it) for clarity.

If
you double click on the 'normal' flow you will see the video running
forward. If you double click on the reversed flow you will see it
running backward.
Now when you run the file you will get an output file that is reversed. Find your output and check that this is so.
All transforms require one input, some transforms require more than
one. Transforms on;y ever have one output. Check on the Gorp Wiki for the list of transforms and what they do. Off you go.......
.... and if you want a transform that does not exist, why not write a JavaScript transform.