U.S. cast members Kevin Clash and Marty Robinson have cast and trained the international puppeteers. At first, Muppet builder Kermit Love constructed the puppets for the new shows in the U.S. According to Gikow in 2009, Jim Henson's Creature Shop, overseen by Connie Peterson, has taken over puppet creation. The producers of "Sisimpur", the Bangladesh co-production, created their own traditional puppets because their puppet-making craft is thousands of years old and an important part of their culture. The producers of each co-production developed and built their own sets, live-action videos, and animations in-country. After they developed, produced, and aired the new show, they conducted research to ascertain whether their curriculum goals were met, just as was done in the U.S. after the first season of "Sesame Street". According to producer Nadine Zylstra, they faced unusual challenges rarely experienced in the U.S. For example, riots and conflicts between Serbs and Albanians in 2004 delayed production of the Kosovo co-production for three months. In 2005, a nationwide strike in Bangladesh temporarily stalled production of their show.