underendered timeline issue

I'm using a g5 dual 2.3/3.5 gb ddr sdram/final cut 5. i have a project i've been working in for weeks now. i have a timeline i've been working in for the last couple weeks., and last week i rendered the whole thing. bascially the timeline is set up as non anamorphic, and the interviews are anamorphic. the reason i'm doing it this way is because the majority of footage we're b-rolling with isn't anamorphic. so for the last few days i've been working off this rendered timeline, adding and effecting new footage and rendering it. yesterday i closed the project like normal, shut down the system. today i come in open the project and most of the timeline is unrendered. no errors came up, no warnings. just most of everything that was rendered is now unrendered? any thoughts on this would be greatly appreciated. thanks

When you added the new footage did you happen to move any of the other footage in the timeline?

Render files are unstable, and so is the connection between the timeline and the render files. What drive are you using as your Scratch Disk? A lot of the time, you really don't have another option except to render again, so I'd just make sure your Scratch Disk has a lot of free space on it, and that you save your project file after rendering.

This might be a great time to run the ever-popular Disk Warrior and maybe repair your prefs...

Sometimes FCP breaks, but sometimes it just gets confused.

thanks for your responses. just curious. in reference to the disk warrior item. this is quite a large project. would you feel it's safe to do something like that mid-stream in this project?