I could use some tutorial assistance in generating a model using BPEL.

I generated a simple model (3 sequential steps + error step, no global data) and tested it on computer #1. Then I exported the model as BPEL and imported the BPEL onto computer #2. I see that the imported model has replaced all my flow steps with WebService steps.

When I try to generate the model I get multiple errors like this:
Error: Web Service interaction and/or operation not defined on step “step1ReceiveService”.

Now what (other than RTFM)?

How do I proceed to generate and run the model on computer #2?