Question1: does the "new" creep crawl onto buildings on low shader graphic settings too? or is it only on medium shaders or higher? or is it purely a terrain setting thing?
Shaders and Shadows have to be medium, Terrain has to be high.
Question2: Is the ragdoll death animation for marines (and maybe other units?) added in the current beta? If is there a certain level of physics setting required to see it? (I haven't seen it once since the beta started on the many streams I've watched).
This is harder to test. Some new physics are definitely in place -- for an example, when killed units will retain their momentum. If you kill some lings with Hellions while the lings are on the run, the Lings corpses will slide across the ground. What settings required, and are new physics used in other ways? I gotta dig through some replays and do some testing before I get back to you on that.
EDIT: No, ragdoll physics aren't added yet.