Hey, newb here.
If I pic whip my Scale and Rotation Values are copied, But I need the values to ADD the same scale rotation changes across multiple layers.
Layer one Scale:1 Rotation:5 --> Scale:3 Rotation:6
Layer two Scale:4 Rotation:9 --> Scale:6 Rotation:10
(both increase by same amounts)
I need to write expression that says "Value of this box + CHANGE IN Value of other layer box"
I suppose what you try to do is modify the scale/rotation of a lot of layers by the same amount. If yes, you need to put those 2 values in an expression controller. If the scale has always same height/width values or has separated dimensions, you could use 2 sliders. So put 2 sliders on a control layer. Use this expression for scale
valueToAdd = //pickwhip the slider one here;
And this for rotation
value+//pickwhip the slider two here
Just replace "//" and everything after with your pick-whip generated code, so final expression for scale should look something like this. The same for rotation.