Nice work on the model Igor, but what a pity about the canopy! I agree with Wojtek though. It looks like it's just surface damage, and with liquid cement probably isn't very deep at all. Polish as Wojtek suggested, and finish off with 'T-Cut' (car body colour restorer) if possible, or toothpaste if that's all that's available. A shine with a soft cloth, then a dip in Future, and it'll be better than new!