My Start8 updated to v1,29 beta last week while I was still using Windows 8 Pro but I noticed that the default icon for the Start button, which was previously the white Windows 8 logo, changed to an odd looking one with a mix of solid and outline squares, which I didn't like at all. The Custom options only have one in blue but at least it is the same design as the white one I was using previously so I switched to that.
My first thought on upgrading to Windows 8.1 Pro over the weekend, which adds a Start button to the desktop, is that the icon redesign was done to better differentiate between the Windows 8.1 Start button and the Start8 one since it is all too easy to click in the "wrong" place and switch to the Modern UI Start screen instead of the Start menu itself on the desktop if you're not careful. I'm gradually getting used to it now though.
So I'm fine with using the blue custom icon but I've noticed that it doesn't quite match the one used by Windows 8.1 so I'd like to see that fixed, albeit it is a very minor thing really, so that only the colours appear to change depending on where you click and not the icon as well. Hopefully, you'll know what I mean.