I have made a model in Creo and try to drive its dimensions from Mathcad. It works the first time but when I modify the dimensions in Mathcad I see no way of updating the corresponding dimensions in Creo. Anybody who know how?
Are you using the latest integration (called the Engineering Notebook) between Mathcad Prime 3.1 and Creo 3.0, in which you embed the Mathcad worksheet, or are you using the Mathcad Analysis Feature?
If the former, you should be able to click the "Save and Push" button (located where the Save button usually is) in the worksheet once you've calculated the Mathcad worksheet and have new outputs to send to Creo. Then, if the relations are set up in the relations table, Creo should display the yellow status icon, indicating that it needs to be regenerated due to new values from Mathcad.
I hope that helps,