Falling box can be compiled now
culprit is predicted to be somewhere related to ProcessCollisionEffects, suspected: mjPhysics
Found culprit: general hiccup at startup

Hiccup guard is needed. Probably also something that waits for time to
be settled before starting simulation
Added Update method to mjSceneManager; added hiccup guard
Removed some debug code that spammed the terminal
Removed cough/hiccup guards from some entities since now there is a general hiccup guard