By clicking on the link below, you will be able to review the latest revision of the International Skat Order. The main change was in section 4.4 Shortening up the Game under paragraph 4.4.5 which states:
A defender may reveal his cards only if the declarer cannot take another trick under, regardless of how the game is played. Otherwise, the remaining tricks belong to the declarer. The Rules 4.1.3 to 4.1.6 apply accordingly.