Unfortunately, I need to make changes to the RMF file format that are not backward compatible. Let me know if you have data saved in rmf that you need to access and I'll work on a work-around. Otherwise, backward compatibility will be lost on your next svn update. Sorry about that, the change is needed to make reading certain large rmf files tolerably fast. The changes will include various other minor changes to make the format more space efficient and support other architectures.