Hey, thank you very much! There's already a patch underway with a ton of fixes, and some of yours are already in there too.
- Normally the game is fullscreen, but with a set size (2000 by 1280 pixels), which probably solves your window issue
- I wouldn't see how to make using items and selecting tiles not require the mouse, honestly. Most roguelikes I've played require the mouse for many actions, though not always as often. Hotkeys and different keys for the same action mitigate the issue a little bit, I hope. (Did you check the Controls in the menu?)
- The patch will stop the player immediately when attacked, yes!
- Damn, memory leak. I did check several classic causes (for example, particles and objects) but nothing there. Sucks, but as you said it's difficult to determine exactly where it's coming from. I'll try to get my hands on it, of course.
- Marked on its own does nothing except attract your Drones, but some effects interact with Marked. The effect tooltip should mention this if you hover over it. If you see nothing when doing that, it's a bug.
- As it looks like now, save and quit won't be a functionality. Probably ever. It's an absolute nightmare to store all variables somewhere, not to mention the darkness shader literally cannot be stored, so that's a big unfortunate downside. Minimizing the window in your version breaks the darkness, this won't happen in patches as it'll be fullscreen, so you can always keep it in the background. Maybe one day... maybe one day.
There's plenty of bugs to go through: using a Blueprint crashes the game, Tripods sometimes don't appear, and there is a 20% game "slowdown" when running. Crashes are highest priority (it SUCKS to lose because of a bug), then content (the Wasteland will be in the demo eventually), then fixes (which I can only do if someone points them out. Like you!). And after release, I'll add some more item sets, particles, enemies... but that's for later.
See you around!