Strange I found this because I kinda like 1.3.1 too (used it until 1.2 patch)

Maybe because it`s mix of both , the SH5 map style on the left and SH4 dials/gauges on the right together in one mod? SH4 style is closest to that setup so I`ll be using that when I start playing again (waiting for more mods conversions first).
Edit: TDW, could you plz link me where to find which icons shouldn`t I use in SH4 UI mod to prevent CTD?