Hi all,
in SCRATCH you can add OFX plugins and Matchbox shaders in two ways:
Either onto a layer of a shot (i.e. pipe the plugin into the shot),
or add it as a new node into the node tree downstream of the current shot (i.e. pipe the current shot/node into the plugin node).
More so, you can add plugins and Matchbox shaders to individual shots in your timeline,
but also to the complete timeline in the form of an output node (or layer on an output node).
Here's how:
Cheers,
Mazze