1. Yes, certain types of objects require more resources than others when viewed on the screen. My experience indicates that the FPS becomes relatively reduced when viewing concentrations of multiple highly detailed objects, i. e. approximately six (?) or more F/A-18Es with extensive loadouts, located on the deck of a carrier in an illuminated state.
Extensive concentrations of relatively complex ground objects, i. e. large factory sites, military installations, airfields etc. may contribute to a reduction of FPS when the specific area(s) is/are viewed.
2. I currently utilize Windows XP Home Edition as my primary operating system, and I can't recall having experienced CTD during operations involving units performing FAC-related tasks.