The OM-D E-M10 needs Camera Raw 8.5 or later, and CS5 only supports versions up to 6.7.1, so you would need to upgrade Photoshop to at least CS6 to use the latest versions.
Alternatively, you can download DNG Converter 9.0 free, and convert your camera's ORF files to DNG, which can be opened in Camera Raw 6.X for CS5.
Thanks. I'm going to trie that. You've been very helpful.