Forum Upgrading from 4.1.12 to 4.2.0
 

I am going from version 4.1.12 to the new 4.2.0, I am about to upload the files and use the overwrite method, however I have custom work done for look and feel and some add-ons, is this going to blow that away? I am a bit scared, never had to do this before and don't want to lose my customizations. Thanks!