The bolts holding the clutch plate on only need 8-10Nm, not a lot by any means.
The AJP clutch master uses mineral oil. DOT4 will do bad things to all the seals. May require a rebuild now A flush or two and you might get lucky.
Did you check the fingers of the basket to see if they are notched? As others have said, its not uncommon for there to be some drag, and not uncommon for the discs to stick if the bike has sat for a while. I tend to grab 2nd gear and rock the bike a few times before going back to neutral to start it. After that it just works.
I thought with the bolts usually you would tighten until you feel resistance then "nip" them up? I got to the point it gave me resistance and loosened slightly, not sure why lol.
How do I go about flushing the clutch system? Do I just "bleed" it and empty reservoir and then fill up with new fluid? What would it be called exactly?