Sorry, correct scale increase applies to *the increase*
Even when my easiness factor was 100 and divisor 100 as well (so the initial score should be multiplied by 1, i.e. stay the same), the correct score increase actually applied to a 1/10 of the current score, not on the increase (which equalled to 0 in this case).
As far as easiness: are you reviewing the card early?
I'm reviewing late. And I have settings not to change anything depending on early/late trigger.
Whatever I put in Easiness change for incorrect answers, positive or negative numbers, I never seen easiness factor to go lower than 100. For some numbers it even rose! What's more, this increased wasn't equal to the actual number in settings...
Also whatever I set for Answer 4 (Barely remembered), it ignores the settings and adds 10 to the Easiness factor...
While I'd like that Answer 4 doesn't change, especially increase, the Easiness. When I enter 0 into the correspoinding settings field, this is also ignored and the Easiness rises anyway by 10...
Feels like the inner math here is pretty complicated and sometimes gives unexpected and unwanted results. Anyway I found some combination of settings which provides more or less behaviour similar to that of Anki's SRS v.2 Scheduler. Which I'll share here after some additional try-outs.