Existing Projects Problem

I updated to 1.5, but now when I click on Open an Existing Project, instead of seeing the list of project, as the previous version showed, my Documents folder opens up and I have to search for a project. I use a PowerPC iMac. Any suggestions, please?

The “Open an Existing Project” button in the start panel is new and has never shown a list of projects; existing projects are listed underneath “Recent Projects” in the file menu.
All the best,
Keith