When working with Windows Workflow Foundation projects, it’s easy to get into the routine of working with your activities in the designer. This is all great and wonderful until the complexity increases. For example, if you have activities that are sequential workflow units themselves, this can lead to some real ‘Workflow Designer Heartburn’. One example, I have a large application with many workflow activities that are sequential workflow units themselves. If I create yet another activity that is a ‘Code’ activity (as opposed to code behind), then the current VS 2008 designer will sometimes just flat refuse to let me drop other sequential workflow code activities into it. To get around this, you can create a code behind activity. For some reason, the designer seems to have less problems with this. I’m just hoping that some of these designer issues are addressed in the forthcoming VS2010.