Default Safe way to do it

1. Root Explorer /system/app change R/O to R/W (From read only to Write/Read)
2. Rename OlympusCamera.apk and OlympusCamera.dex to OlympusCamera.apk.bak and OlympusCamera.dex.bak
(#2 Depends if you are dex or undex) just need to rename all OlympusCamerca.* to end .bak
3. Unzip new file and copy OlympusCamera.apk to /system/app (Root Explorer is tricky because everytime you long press it to copy it show up install option... DO NOT INSTALL.... best way to copy use ADB shell
4. Change permission to OlympusCamera.apk to rw-r--r--
5. Change Mount R/W to R/O (optional but safe)
6. Reboot and clean dalvik cache, or just delete OlympusCamera dex entry on Dalvik Cache
7. Enjoy it!