4.16/17 Crashes enabling 'Raytraced distance field shadows' (Mac)

Hi all, I have a project on a iMac (5K, 27-inch, Late 2015, 4 GHz Intel Core i7, 8 GB 1867 MHz DDR3, MD Radeon R9 M395 2048 MB) with a project running smoothly, its only dynamic lighting no issues except for when I try and enable ‘Raytraced distant field shadows’ which immediately crashes the editor in both 4.16 and 4.17 (the crash report is below) however if the shadow quality is set to only ‘High’ then its fine, but as soon as I switch it higher than this it crashes again, I thought it might be overloading the Mac’s tiny VRam but the crash report says it cant find series of files, does anyone know what this might be?

You need to go into the project settings and change the Metal shader standard from v1.1 to v1.2 - this will require a restart and to recompile shaders. This setting uses newer Metal features required by Raytraced Distance Field Shadows, amongst others and therefore raises the minimum macOS requirement to 10.12.

Thanks for the prompt response, that worked perfectly!