Lets talk BYOB. We are guests of Pheasant Run. They make revenue selling adult beverages. This requires a liquor license. There are rules involved in this.
Here is the short answer. In your own room, you can enjoy a bottle from any source, including your own still. Outside your room, ie halls, tent, grounds, etc, you can enjoy whatever Pheasant Run has to offer. Commercial sponsors, if you are renting a larger space and have questions on this topic, feel free to contact Pheasant Run.
Also, if things get out of control, there are members of the St Charles police force on site, guarding the Mega Center. Don't get silly.