Using svg images for the first time, and while placing them on the advglowbutton was easy - my expectation was that the svg image scales with the button automatically - but it doesn't. I can set the size with picturewidth and pictureheight manually though, but I rather would like to see the scaling according to the buttonsize automatically.
Is that possible?
At this moment, there is not a setting to have this automatically.
This is a good suggestion though that we'll consider for a future update.
This is unfortunate - realistically how long do you think until you can implement this? (ah - this question again :( ).
How can I motivate you to implement this in the next version? Buying another license? 
We will offer a first step in the next update where it will take the button size with settings PictureWidth = 0 and PictureHeight = 0