This is the monthly update for December.

The main feature of the December update is the new Checklist. It is meant to act both as a tutorial and as a reference guide. There are over 50 items to complete, taking you all the way from gathering the first resources to launching a rocket.

There are a few other changes and improvements as well, here's the full list:

Changes
- Added Checklist feature, as described above.
- Made some changes to the hydroponics and compost projects. In particular, a project is now required before hydroponics planters can be constructed. *
- Removed New Game and Load Game from the in-game options menu. **
- Wall UI has button to convert to door, and door UI has button to convert to wall (previously conversions were only possible using the construct tool).
- Can now lock doors open or closed.
- Added a light to the door (red if locked, green if unlocked, yellow while opening or closing).
- The default temperature range for the environment control is now 0 to 30C. Unless the room has crops or an algae pool then you probably don't need to change this.
- Also changed the min and max temperature ranges. Min can be anything from -10 to +36C, max can be 0 to 40C.
- A colonist working at a lab won't prevent another colonist from using the same tile to access a dispenser.
- When attempting to place a water pump or mine, a production rate or resource count is shown even if location is not currently buildable.
- Added warning by mouse cursor when using deconstruct tool on plants which are fruiting or may do so in the future.
- Stacking areas default to target stack size instead of target silo level (figured this is probably the most intuitive option)
- Escape key now toggles the options menu if nothing is selected and no other UI is active.
- Made the remaining buttons on the in-game options panel very slightly bigger.
- Options menu can now be controlled with keyboard. Also buttons can be selected with mouse wheel.
- Removed the code that automatically hides the options panel after a few seconds.
- Renamed the engineering project Hydrogen Storage to Hydrogen Fuel.
- Tested some old saves and found that those from the very first Steam release - v0.1 - no-longer work. Couldn't easily fix so these are now marked as incompatible.

* - Hydroponics planters are now locked behind a project. I realised that new players are ignoring mush and building planters early on. In a way this does make intuitive sense, but it's actually not a good strategy - it takes too much metal and crops take a long time to grow. On day one, harvest as many bluefruit as you can, then make mush when these run out. Save your metal for a power plant. Don't bother planting crops until the morning of day two.
** - Why have I removed the new and load game buttons from the in-game menu? The code around creating and loading games is some of the oldest in the game and it needs some work. Having only one entry point - the main menu - will make this easier. If anyone asks then I might put these buttons back later, but to be honest I don't it's going to be worth it to save a couple of clicks on something you're unlikely to do very often.