In fact this should be the rule for new comers and beginners :
Learn lua ... Learn the API ... then write this stuff ... Simples.
I passed the all the night re-learning Lua and how it works digging what i could understand in Goblin,player,camera code
This morning i learned Flowgraphs and use them already and I am making a complete LUA game,
A link that should be pinned for Lua users :
http://www.leadwerks.com/werkspace/topic/6027-leadwerks-3-how-do-i-questions-and-answers/page__st__20
Keep it simple, try some bits of code, try some code from tutorials section etc ... try some physic functions, read examples.
Step by step you'll have all basic Lua programming in some days, and also how to do program gameplay and 3D stuff.