Hi! I'm new here and I'm not a technician. 
I am neither English nor American and English isn't my native language (I am Russain living a long time in Norway), so I'm sorry for my poor dictionary.
I have been using Studio three years. First it was Studio 10 Plus, afterwords - Studio 11 Ultimate. I made one big project with Studio 10 and one - with Studio 11. Until now I haven't had any big problems with either of Studios. But now it goes wrong like hell.
For some time ago I made a project with the Studio 11 called Paris 2007 and everything was OK - I created a DVD and had fun. The project is saved in "My Projects" folder on my computer's harddrive, it contains either the project file Paris 2007.stx and project folder file (a grey one) with the same name.
When I tried to open this project for one week ago something strange happend. In the window "My projects" I choosed "Paris 2007", it came a new window - exactly the same, but in the file name field the name of the file was NOT "Paris 2007", but some strange "THE END.mpg" (I suppose because the final credit of this film was namely "The end", it's an animation imported from ArcSoft moviemaker program). Clicking "Open" this file gave no result. It came the same window with the same file name in it. When I pressed "Skip all" the project "Paris 2007" opened, but it was impossible to edit it. Nothing worked - the preview didn't go, it was no sound et cetera.
After a few hopless tries I contacted Live Chat. Such chat sessions I have had 6 or 7 in theese days. They gave me some instructions like update the drivers, shut down all background activities, antivirus and messengers, 10 - 15 issues I should do to succeed. I did everything, but with zero result. Paris 2007 doesn't open now at all. It seems like a mystery!
I uninstalled and reinstalled The Studio11 twice. Nothing helped. I uninstalled/reinstalled the hole Window XP. The Paris 2007 doesn't open (exactly the same situation as described above). I uninstalled Studio 11 and installed Studio 10 Plus I worked with before. I gave up to open Paris 2007 and made a new project called "Kiel".
Everything was all right until I came to "Make movie" process. Fortunately, I created a Windows video (AVI) out of this "Kiel"-project, otherwise I could miss this project totally too. Trying to create a DVD-film from this project was failed. Studio 10 didn't want to make it. 
It was late and I went to bed and today morning I tried to open project "Kiel". Again it happens something strange, this time with the Studio 10. It opens the "Kiel", the right name comes on the project-window (on the top-left corner of the screen), but the Storyboard line (and of course, Time-line) is absolutely empty, no clips, "no nothing".
I tried to explore what happened. I made two small projects called "Probe1" and "Probe2", both contain just three clips with 2 transitions. Saved them in the same folder as "Kiel"-project. Now, when I open theese two projects they come like angels - everything is all right. But when I try to open "Kiel" - it comes the right name "Kiel" on the project name-line, but the clips on storyboard-line are from "Probe1" ! Sometimes the name appears like "Kiel-1" with the same content on storyboard-line.
I am so desperate now, that I gave up the hope to make movie sometime in the future again. Can somebody be so kind to help me Please??? It seems like Pinnacle support doesn't borther.