Here's a few more:
How are fumble results applied to the character?
Exactly the same way a critical result is applied. Once you roll a fumble result, and click done, the results are applied to the player in the case of the fumble, not the target. The procedure doesn't change other than rolling the fumble result. You can alter the fumble result as well the same you can alter the critical result.
How do I reduce the rounds of stun if the character succeeds the Stamina RR against them?
Select the character and by using the Character panel located on the right side, go to the stun value where there should be a stun value and adjust as necessary.
Are the effects of stun (+20 OB, parry at 50%) applied automatically or do I need to apply them manually?
Looking at the application it does calculate the parry at 50% if stunned but it didn't give the player a +20. So I have now added that.