If you followed the instructions listed for Mac in this FAQ it instructs you to copy the files to your computer first. If you did this the data should still be on your computer. Where did you restore the data to?
Also there is no file size limit for SecureAccess 2.0. The only limit you could have possibly ran into regarding file size is the FAT32 file system limitation. The FAT32 File system cannot store any single file larger than 4GB however since your drive is in FAT32 anyway there would have been no way to have a single file larger than 4GB on it in the first place. I do not think the 4GB file size limit with FAT32 has anything to do with this.
