Yeah as the title says are there any bonuses if one preorders this game throgh GoG ? Thanks

The only thing that MAY relate to pre-order bonuses are the extra digital goodies listed on the product page. It tells you what you get with the game, then it mentions digital extra's. It doesn't specifically state that they're for pre-order, but they may be. Until GOG says they're for pre-order only I would presume they're not, in which case there are no "special" pre-order bonuses..