I am working with CS6 Production and I am having the same problem. I have tried to do this since adobe added Project Manager to Premiere and it has never worked. I have always gotten this error. Has anyone every used project manager successfully?
I have always attempted to save the new trimmed project to an external disk – could this be the problem? (Plenty of space USB 3.0)
Do you have to save in the same location as the original project file?
If it worked it would help me out so much.