The simple answer is that you don't need to use a sequence structure at all. Just lay out all of your functions horizontally and connect your error in/error out and VISA connections between them. In most cases, the sequence structure just serves to hide your code without providing any real advantage. If you need something a bit more sophisticated, the the state machine architecture is much better. There are a couple of shipping examples and you can also search the Developer Zone for more. Bascially a state machine is a case statement inside a while loop. A shift register or a queue wired to the case selector determines which case will execute.
