@Hyperplexed: Thanks for the suggestion :)
Tried around with a few alternative drivers.
- Latest beta driver from Intel
- Latest modded driver from Intellimoders
- Latest driver provided through MS
Same issue.
Just out of interest I tried running SSE on an older laptop with Intel HD 4000, naturally it runs like $£€£, but no gfx glitches.
And after googling around a bit for other reactions, I think that this issue is an Intel HD 5XX (Skylake) driver only thing.
..and waiting for Intel to update their drivers is .. meh! xD
You mentioned that this looks like the renderer/shaders duplicate mesh issue. Just wondering if there would be any settings in the config files worth playing around with (turning off)?