I've a question about Tekla Open API. I've created a contourplate using the Tekla Open API in Visual Basic and now I want to add a beam to the contourplate as a sub-assembly on a lower level in the assembly hierarchy. I'm however able to add the beam to the contourplate without any hierarchy. I used the following article to do that http://software-solutions-online.com/tekla-open-api-cast-units/ . I hope someone can help me solve this problem.