Hi. Just tested it with max 2020 and Corona 8.2, and it seems to work as expected.
Remember that "Map fixed" means that black will be "From" value and white will be the "To" value. But with "Legacy" black will be 0% and white will be 100%.
Your scale-settings is from 40% to 50%, so "Map fixed" will be less visible than "Legacy".
Hope it helps