cannot set mlraw as default app on a mac

I've been trying to set MIRaw as the default app for opening .RAW files but I'm getting an error (-10813). I've tried onyx to repair disk permissions, disk utility to repair the disk and terminal to reset the lanch services, as seen this has helped other people with the same issue. I'm using Yosemite 10.10.1 and the latest version of MIRAW. Many thanks,