score:2
It appears that Slovakia does not celebrate Mary's Assumption, unlike Austria:
http://en.wikipedia.org/wiki/Public_holidays_in_Slovakia
http://en.wikipedia.org/wiki/Public_holidays_in_Austria#Austria
So, it's pretty safe to say that shops and museum will be open in Slovakia on the 15th of August.
Upvote:2
Yes, on 15 august shops in Slovakia are open, and other places like museum also are open.