A man goes back and forth, slowly, silently, carefully balancing framed paintings and works on paper. He transports them from a pile perched atop a canyon to a Mondrianesque storage grid positioned on another peak nearby. From beginning to end, he walks on a tightrope. Shot against the spectacular background of the mountains of the Caucasus, the 73-minute video Tightrope (2015) by Daghestani-Russian artist Taus Makhacheva is a natural testimonial for “Lost in the Archive,” a group show organized by the Latvian Centre for Contemporary Art (LCCA) at the Riga Art Space, a vast underground exhibition hall at the heart of Old Riga. Tightrope is a clear, visually powerful allegory for the difficulties of juggling with heritage and memory, of performing and preserving them, and making them travel across time and space. A tricky exercise, especially in the context of a “peripheral” post-Soviet culture which allocates modest means to the task. The artworks are reproductions of the Daghestani Museum of Fine Arts’ collection from the late nineteenth century to the year 2000. By contrast, the almost invisible installation Untitled (from the series “Cannot Think in Words,” 2016) by Lithuanian artist Žilvinas Landzbergas, who mimetically dressed up a few of the gallery’s columns …