Broadly, the danger level is stress/material_strength (by some appropriate metric). Thus, when displaying the danger level, red corresponds to "bad" when the ratio (stress/material_strength) is approaching or exceeding 1.0. The more there are areas that have stress exceeding the material strength, the more there will be areas that show up red. If the part is lightly stressed, the danger level will be in the blue area, corresponding to "ok". Eventually, we will allow the user to specify a factor of safety multiplier and choose their own ideas of "bad" and "ok".
The report contains the actual maximum value for the danger level.
Still not sure whether this is a bug.
If not, I find this way of presenting the "danger level" rather un-informative because there is no way to spot the exact zones which are avove the acceptable level...