Are you sure that
a: that you've got the -show_err thing right
target line in shortcut properties should read ......RomeTW.exe" -show_err
and
b: that you have re-deleted your map.rwm in the campaign folder (and for luck have you deleted the map.rwm in the base folder)

I've tried it under 1.0 which is closest I've got and it's generating error messages when you quit program after kick back to menu, first was couldn't find roman_generals_guard_early (probably 1.0 has different EDU) fixed this then it complained about port at 80, 121. Not sure how to fix that except by trial and error as 1.0 doesn't seem to generate corrected_regions.tga

but this does seem to show that after fixing map_roughness size you should at least be getting error messages (or you've done something 1.2 specifically objects to).