With regard to warnings menu- for different thresholds, color of font will change, but when I edit the message for each level that message is global, I would expect the text message to be changeable for each warning level.
This actually has been on our todo list for a while, but will only affect if text is set to ‘static’. Maybe I will try to push this to next release (1.6.2).
This same effect is possible by having 3 different text gauges and just set the text color to fully transparent on levels that you wish not to show them.
Edit: Just pushed 1.6.2 beta 2, which includes this fix.