Winderwood

I'm fairly certain this is a problem with VRAM (Video Random Access Memory), the same effect can be seen on other games if your VRAM can't keep up with the texture streaming. There's not much that can be done about this if VRAM is indeed the issue. The only immediate fix I could suggest is trying to play at a lower resolution or at lower graphics settings. This could also possibly be solved if the devs better optimized the game textures, although that would only go so far, hardware would still be a big bottleneck.

This looks like a very exciting update, I can already imagine thousands of new possibilities with this new editor. I do hope that it'll be possible to set plain colors on the objects (red, blue, green, orange, purple, etc.) rather than just materials, since the materials probably wouldn't look right on complex objects. Also, as someone else mentioned, that it'll be possible to assign sex poses to objects you place, although that may be asking a little too much from the first release.