I know that the resources are loaded during the start of the game.
But how to update game resources without restart game? (more interested a gfx)
If it is possible through Lua or Delphi?

Sorry if this is a silly question.

No, all resources of CS2D (gfx,sfx...) are loaded on game start. You simply can't reload it.

Very sad, I think that can somehow interact with the process of the game, to update resources

You can't do it without cracking.