So I actually asked via email and got a response from the developer. I guess that makes it all clear now. Thought I’d post it here too, in case someone ever has the same question again
‘“Remember Resize Interpoation” - save “Interpolation” value used in in Image > Resize Image, even after you restart the app. If off - Interpolation will be set to “LInear” after app relaunch.
“Remember Transform Interpolation” - remember Interpolation used in Edit > Transform
Maximum Velocity - it is used when using brushes with “Velocity” dynamics, for example Pens > Velocipen. It says how fast you have to move your Pencil/Finger to achieve the max dynamics effect.
In Velocipen - how fast you have to paint to achieve the minimum stroke size.”