No luck again. Used MC64 V2.0.171. Again deleted the build tools, downloaded the latest build tools from within MC64 and tried to build (Clean Compile):
Compiling Mame...
Using Parameters PYTHON_AVAILABLE=python SHELLTYPE=msdos -j6 NOWERROR=1 TARGETOS=windows TARGET=mame SUBTARGET=arcade OSD=windows PTR64=1 STRIP_SYMBOLS=1
GCC detected
Converting src/mame/layout/18w.lay...
Converting src/mame/layout/24cdjuke.lay...
Converting src/mame/layout/280zzzap.lay...
GCC version 4.9 or later needed
make: *** [build/projects/windows/mamearcade/gmake-mingw64-gcc/Makefile] Error -1
make: *** Waiting for unfinished jobs....
Converting src/mame/layout/30test.lay...
Finished!
0 Hours 0 Minutes and 1 Seconds Elapsed.
Hitting GO! again did not fix it:
Compiling Mame...
Using Parameters PYTHON_AVAILABLE=python SHELLTYPE=msdos -j6 NOWERROR=1 TARGETOS=windows TARGET=mame SUBTARGET=arcade OSD=windows PTR64=1 STRIP_SYMBOLS=1
GCC detected
Converting src/mame/layout/ace.lay...
GCC version 4.9 or later needed
Converting src/mame/layout/aces1.lay...
Converting src/mame/layout/acrnsys1.lay...
make: *** [build/projects/windows/mamearcade/gmake-mingw64-gcc/Makefile] Error -1
make: *** Waiting for unfinished jobs....
Converting src/mame/layout/aim65.lay...
Converting src/mame/layout/aim65_40.lay...
Finished!
0 Hours 0 Minutes and 1 Seconds Elapsed.