Honestly, I'm not really sure if the problems are solved from here. No one even replied to this message for 2 months and I don't trust them anymore.
I do have the same problem, both on my laptop and my desktop. It works OK on the first material change, but crash on the second one. If I undo (ctrl+z) after applying a material, I can choose another material again. But this scenario is not always applicable, especially if you want to change the material later. Seriously, the problem is still there after 2 months, while it is very easilly reproductible... to be that means bad/missing debugging work.