About 1 in 10 males (whether they know it or not) are color blind, with red-green colorblindness being the most common. One side effect of this is that red might not stand out from dark grey or black.
I fall into that category.
In the this first beta of Photo Mechanic (5.0, build 12738), I find it very hard to read the red file names (when the data for the image has yet to be loaded, I think), and, more importantly, the red underline for misspellings in meta data doesn't stand out well at all against that dark background.
I see that there are options to change the colors for the contact sheet, but it would be a much better user experience to not force a new user to find that option and change the colors just to make that status indicator usable.
However, I do not see options to change the colors of the IPTC Info dialog, or the color of the underline for misspellings. This is a problem. It makes the really nice feature of showing misspellings in meta data mostly useless to me.