So you want to replace one step with a step of a different type while the sequence is executing?
If I am understanding you correctly I would advise against this as it would be the equivalent, in my mind anyways, of writing self modifying code. However if you simply want to change a module, VI, dll, seq etc that is being called dynamically then you could modifying the properties of a step. Could we get a bit more information on what you would like to do?
