Hi and thanks for the feedback!
I will look into adding video playback support very soon so it should hopefully be back in a few weeks if nothing goes wrong.
The engine is written in C++, if you are interested you can send me a private message(Via Discord for example) and I could also share the source code with you.
Lua is the scripting language of the engine. It is optional, all core features should work without having to use it but it can be used to extend the game.