2018.x SBSAR Files (Will Be Fixed At Some Point...)
.sbsar files won't work in 2018.x yet.
Copy This To That (All Versions)
If you copy all actions on a script that has a lot of "Procedural Materials" on it, it'll take a long time to complete. This is because Unity is doing everything twice, in order to save the changes. It's an annoying thing, but just be aware that it'll take a while to complete. Uncheck "Save Changes" in the Options area of the latest versions of the script to speed this up. But if you quit, any changes will not be kept.
Mass Exporter Won't Work (5.4.x)
[LATEST: 5.5.0b6 has a fix! I've not yet tested it, but I've been told it's fixed! So 5.4.x will *never* work with the Mass Exporter, but 5.5.x seems like it will :D ] https://unity3d.com/unity/beta/unity5.5.0b6 Currently "Mass Export" doesn't work in 5.4.x because of a Substance bug that adds " (Clone)" repeatedly to the end of the file name. Allegorthmic is aware and is working on a fix for a future 5.4.x update. Current 5.4 versions will never work with Mass Export, though. :(
Mixers can be pre-saved, or you can script snapshots to be faded in or out depending on what's going on in your game. Perhaps, for instance, a low-pass filter is applied when the game is paused, or the percussion grows louder when a Boss is being fought. You can adjust each layer individually to craft the perfect sound for your game. A Master track -- consider it the "Composers Cut" is also included if you do not wish to mix the track yourself.