Nicholas, one thing you might want to try...

1) Create a small executable that runs the report and generates the output to PDF

2) Assuming you're using SQL Server, you can create a job in Agent. You can create a step in the job that points to an operating system command or executable, and then set up a schedule for the Agent Job.

Different question - does the report have to be in Crystal? Only reason I ask - scheduling a report to run as a PDF in SSRS is even easier. But if you need to stick with Crystal, you might want to give these steps a try.