I have paint dot net but have not really used it - it seems I have to look into now. Its been mentioned in a few posts recently and with regard to your comment it seem it will worth it.
I must be the Luckiest Duck on the Planet . There is no way I can make a blur from anything I use for drawing normally . That is because I only ever drew stuff for CNC machining and 3D Printing . Some one gave me a Very old copy of PS ( Photo Shop ) and to be honest that is the only thing I use it for . I make a White copy of the Shadow Shape I want and Apply a little Gaussian Blur on them . I have Found I only need a little . As was mentioned apply them Below hands and above LEDS . I then Tint them and vary the opacity till they look good . I usually offset them -2 pixels X and Y because I am Fond of the 3/4 lighting that Facer and my CAD use by default . Most Decent Graphics packages have a Gaussian Blur Setting . It is as with everything finding it . It is well worth the effort . When you have Mastered It you will be Very Pleased .
I just updated to V 5.1 and had a look . Gaussian Blur radius 10 seems fine to me for a shadow . A nice glow for sun or moon might be bigger . It is always surprizing when you add a bit of Opacity in Creator .
.
.