Wow, thank you so much! It's hard to summarize the work I did. Knowing a lot of quick tricks and shorthands for various features helps a lot.
I also avoid putting mechanics into my ludum dare games that I know I can't pull off quickly. Menus, cutscenes, inventory, and gated progression I keep to an absolute minimum. LCD only contains one cutscene (the credits) and one progression barrier (the crystal), so it was very easy to playtest.
Was there anything specific in the game you wanted to know about?