I guess I'll kick it off!
It's super bare right now, but I've got things like selectable elements going, along with highlights, also the fixed camera that'll only move up and down between two points (dont want the player zooming their camera off into space). Still, doesn't have to look pretty yet, it just has to work!
Also it's kind of hard to see, but the mirror on the right is selected (it's got a red light that turns on when it's selected), and the top left mirror has the mouse cursor over it (pinkish light that turns on and off as long as the mouse cursor is hovering over it). Bottom left is what mirrors look like when it's not selected at all.
All in all I'm surprised at the amount of progress I've made so far, considering how long it's been since I've actually touched a game engine, but it's coming back to me slowly lol.
Can't wait to see what others have done!
Also, I recommend a program called Gyazo for taking quick pictures of your progress. It binds itself to your printscreen key, lets you drag out a rectangle and it'll quickly upload the image to its servers. Then you can right click the image it uploads and select that image url to use here, it gets rid of a whole other step of saving and uploading a print screened image lol.