Just an added feature that I recall doing was to sift the p.o.p when I was dealing with small legged bugs, may sound a little to extreme but the end result showed the difference.
I only made a cube mold for one to three bugs at the most which having better outcomes.
the last was went to using a petroleum jelly for a better release factor instead of worm oil and at times used both.

Now here again from remembrance this seemed to work for me.

billygee :rolleyes: