the frequent lag-skips to the left/right make the character completely uncontrollable. (and have caused all collisions with enemies I have experienced so far.)
I've just uploaded the latest version (as per the exchanges with Boopy2), which includes health restoration at the beginning of each level.
I am not sure about restoration at each checkpoints, but if not, it's probably then sensible to add in the main menu a load level option to restart the current level. I will play a bit with it and experiment to see what can be done.
And thanks again for giving me feedbacks :D
I've tried it on my home PC again and it seems that you may be using a few synchronization calls too many per frame.
You may shave of some cycles if you wrap the sync-call routine into a function that checks if it has been called before in the current frame and only updates the sync variables during the first call.