Setting an entity unbreakable

[Apjjm]

If you plan on having multiple bottles, the best way is just to make a custom entity.
To do this, open up the bottle's .ent file in the model editor, and use save-as to make a copy with a different name (It might be worth making a folder called Custom in your entities folder to put your custom entities in, so that you can just copy this into your CS entities folder when you are ready to release the story).
Now you are working on a copy, go to settings->user defined variables and scroll down to you see the checkbox that says "BreakActive". Uncheck this box and save your entity.

You can then navigate to your custom folder in the level editor to place your custom bottle prop which won't break.