Question about Knytt

I was wondering how some of the lighting is done in Knytt.  Specifically that above lava and such.  It shows as a gradient but going into a transparent color.  In MMF, it show this "glow" above the lava objects but there is no object there.  I am having trouble finding how this is done.  I know this forum is rarely used but any help would be appreciated!  Thanks so much! 

a completely uneducated guess would be something related to having a lava object that has an alpha-channel gradient at its top.

The two possible answers I can think of is first that the object is locked, or positioned in a layer that is locked for editing. Try to unlock all objects, or all layers.

Thanks Nifflas.  It was on a locked layer and I was able to see how it worked once I unlocked it.  It seems that it uses the "Add" ink effect that I was not familiar with.  I learn something every day