If you want add your own avatar scaler you do it in 4 steps:
1 - the first you should click on the button 'debug'
2 - now you should open 'debug 02'
3- choose 'Scale AbsoluteX', or 'Scale AbsoluteY' or 'Scale AbsoluteZ' this is the height width and length
4 - click on Override, if you want small avatars you should add numbers from 0.01 to 0.99 if you want big avatars you should add numbers from 1.01 to ...
for example 1.0 - is normal size ( 100% ), 1.5 its 150% avatar, so its avatar which has a height of 1.5 normal avatar