I wish that it will be possible to minimize the Key app to the tray/notification area on the taskbar.
Key is a new product and there are some idea suggestions for it which can be found here:
Other users can vote(Kudo) for the ideas they think are good.
In your case I believe a moderator will move your post to the Idea Exchange forum. Probably not until tomorrow though.
We are looking into implementing "Minimize to systray" for Windows in future releases.