Amazing answers you said the things i was wondering and having thoughts about and the plug in the mold is smart so that the silicone can be pulled out and collapse inwards when removing the cast. Also the cut and white glue in the cast form is very smart since the "flash".
So far i had very few successful casts but those attempts have been without vaccum for removing bubbles from resin before pouring and without pressure chamber for curing to reduce and get rid of any bubbles.
I will look into the pressure and vaccum chamber now.