Help in GameMaker

Share your creations!
A little question here. May I publish game now,but then constantly update it until 14 august?
"The game should have local multiplayer OR be designed to easily include local multiplayer."
can that means i can create a server without using html5 project?
About the OperaGX Game Jam. I made a game that can be seen only by dark theme users. I have no idea how to make it adapt to light theme automatically so I was wondering, can I upload a separate version of the game for light theme users?
Hi there, where can I find the graphical-guidlines for the "UFO-Theme"? Thanks! :-)
