Thanks a lot for your information.
We can reproduce the issue in our tests now. The problem is the program can not handle more than opening 512 files. Since your projects contain a lot of edited video/audio segments so the issue occurs. You can use the temporary version at https://drive.google.com/file/d/0B3hOg7Fkv-dvcm1JdENON2FXYkk/view?usp=sharing which supports up to 2048 files.
We will try to fix this issue in the future release.