Specifically the software "Кристалл" (Crystal) used for 3D furniture modeling, interior visualization, and calculating material costs (often sought in Russian-speaking design communities).
To help you better, please clarify which of these you are looking for:
Could you let me know which of these you meant, or provide a bit more detail about what the program is supposed to do?
This request is somewhat ambiguous as could refer to a few different things in the context of downloading software.