Prevent Alumilite Amazing Clear Cast from sticking to glass?

You would be better off using the silicone instead. Because like you said - it will bond to the glass so if you try to break the glass you will actually be breaking the resin. Or you might not even be able to break the glass at all.

There is pretty much no way to prevent the resin from completely bonding with the glass which would make the removal of just the glass impossible. If you just need the silicone mold to be a little smaller than the liquor bottle then there is a way to "shrink" the mold itself while making a mold of the skull but other than that I would not attempt to pour resin into the skull and expect to be able to remove the glass from the resin.

I would just make the silicone mold of the skull and don't even try the resin.

It never hurts to ask - it's what the forum is here for. Sometimes I ask just to be sure I'm doing something right or to get another view of a problem.

Once the resin is poured and has fully cured, it's considered "stable" and should not break. I keep my castings and mold boxes in a room that is fairly un-insulated and have not had a problem when the room reached below freezing several times - the clear has never even cracked from that. The glass probably broke due to a quick change in temperature which is what glass will normally do especially if it's thin or it's not "tempered" glass like a window pane.

If they are coasters, I'm assuming they'll be used inside so you should have no worries about them exploding due to a temperature change. Other than that, I am 99.9% sure you are safe in pouring resin onto and over glass and don't need to worry about it exploding.

If anything breaks, I'm fairly sure it would be the glass and not the resin - I've used the Clear on some of my mold box bottoms to level out the bottom or fill in any cracks under the castings and on one of my most bought molds it is just now starting to have problems due to my rough handling (I'm very rough on it too) and to understand how long it lasted you have to know that I've made this mold design over 10 times. This is a thin layer and the Clear can really handle not only the temperature extremes but all the prying and flexing I do to it so a little thing of shipping them and regular use should not make them explode or break unless the glass itself is what breaks.

Now I would not be dropping them from like 3 stories high just to test that out or baking them in the oven then pulling them right from the hot oven to a 70 degree room. That's stuff that would cause the glass itself to break and it wouldn't be the resin's fault. I hope this helps you.