Thanks SDK. I remember reading functions worked as variables, but didn't know that they could be overwritten that easily.
As for the second question, in Pawn, when you included a library (which is similar to a "resource" that provides functions) and wanted to use a callback (event) such as onPlayerConnect, you would need to "hook" the callback in the library. For example, if in the main gamemode script someone had onPlayerConnect callback, and the library also used the callback, then you'd have to hook it, or call a separate function (such as onPlayerConnectEx (a custom function)). The method of hooking would eliminate this, so when the main gamemode script read the onPlayerConnect callback, it would also automatically call the one from inside the library. (It's not as complicated as it seems, I just can't find the right words to explain it)
However, I don't believe that will be a problem, as resources are used differently, in Lua. I'm assuming I could run a separate resource with an event, regardless of whether or not it's already in another resource (like a gamemode)? If so, I don't need any guidance on the second question.
Once again, thanks, it's much appreciated! If I have any more questions, I'll post again.
EDIT: I'm sorry, but I missed the whole reason I posted in the first place
Included in my first question, I meant, is it possible to replace the function with all functions not only in my resources, but all that loaded on the server. So if they included my resource, then all of the resources that use that function will call the "hooked" (or custom/replaced) function.