I ran Pro|Mechanica for years (now Creo Simulate), and whenever there was an error during meshing, a warning message would pop up and state, "The highlighted elements......then whatever error after that". However, there would never be any highlighted elements in the display. Then in Creo Simulate, they seemed to make some improvements, and the element, if it was on the surface of your model, would be highlighted in red if is was not valid. But what about elements internally? You cannot see them unless you shrink the elements. Now, to your question, I do not know of a tool that will highlight bad elements during validation and hide the good ones, but I will look at it, as I do not run simulation any more, but did for about 20 years. Always something new in Creo. Now you stated 100000 + elements in a model? That's scary. No wonder you cannot rotate it.