Is anyone able to confirm how SD calculates contingency fuel?

Reason I ask, I have 10% set in the aircraft profile for IFR, and if I set an Alternate, then it seems be calculating 10% of Cruise+Diversion.

Is this a fixed-wing thing? Most rotary ops manuals I have seen just calculate 10% of Cruise only. Is there a way to set it up for a Cruise only?

On another note, in the aircraft profile, the lowest value allowable for Holding Time is 10min. I would like the ability to set this to zero.

Cheers