When you install Bitwig, check your previous version/files, because if you made your projects on Bitwig 3 and then you install bitwig 2.4, it won't open your projects from 3.
Tracks greyed out, upper left of arranger (below 4/4 and bpm) there's a box with like 3 grey lines: click it
Switch to PulseAudio so you can have multiple things playing audio at a time (48000 worked for me for less crackliness)
VST plugins, where to put them.
Create multisamples in Bitwig
https://www.youtube.com/watch?v=2_9kbGYzSbQ
Create a new Sampler instanace and click ‘create new multisample’ on the unit.
Just drag the set of files, so long as they're convention-named like ‘V1 C2 TheSynth’