If you have no mods installed the easiest way is to upload RC4 (except config.php) over your current files and then run database_update.php from the install folder.
If you have installed any mods then you will need the changed files and you will have to do a compare of the changed files with your files. Again you will have to run database_update.php. You will need to make sure that any mods are RC4 compatible.
Also remember that if you have installed any styles you will need an RC4 compatible version.
Remember: You only know what you know and - you don't know what you don't know!
My CDB Contributions | How to install an extension
I will not be accepting translations for any of my extensions in Github - please post any translations in the appropriate topic.
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