Anyone using S1 Project for mastering songs not created in S1 needs the option to directly replace an audio source file without changing any of the plugin settings or metadata! Should be as simple as right click audio file -> "replace". Similar to what is mentioned here in another forum: Replace Audio File In Project. This is imperative if you are using this program to create DDPs for clients, etc. I can't believe more people haven't been asking for this. Project could be such a useful tool, but is still fairly elementary at this stage. It should not be limited to use for only songs created in S1. This would be a step in the right direction.