Problems with Mapster index sheets have now been fixed.
We have added up to 50 sheets of the Austrian (KuK) "Operationskarte" 1:400,000. The 300 dpi sheets come from a digital library of the Polish Academy of Science, those at 400 dpi are from private collectors and, through help of  easteurotopo.org site, from the Library of Congress.
We have also added a few town plans: Köslin (Koszalin), Belgard (Bialogard), Sopot – all in the Pomorze (Pommern) area of Poland, Kostrzyn (Küstrin), and Klaipeda (Memel). More (many more) town plans will be made available after summer.