Hi,
The custom action wizard lets you build the skeleton of the action, not the actual "content" of what it will perform.
implementing scripts really depends on what it's actually doing. Can you share the script you want to port? This will give us a better idea s to how to port it.
Also, look up this forum for javascript actions, they are some, currently the wizard creates c# scripts, not a big deal, porting javascript to c# is not difficult at all.
bye,
Jean