What kind of acrylic is it? Cast or extruded?
There’s a big difference between the two as far as machinability. You want cast.
As far as melting and burning goes, try slowing down spindle speed and upping work speed.
You might need different ones for for engraving and cutting. Just have to play around and see. You can make a test in Luban by creating a line and then duplicating it several times and setting different speeds to try out.
Here’s a good thread:
-S