Raised access tile supports are fitted with narrow fins that are spacers between the tiles, creating small gaps (like grout joints) to allow drainage. Tiles are pushed firmly against the fins and cut to size at the edges to enable a jigsaw puzzle-like tight fit.
Do not glue the tile support to the membrane, this would damage the membrane and compromise the accessible nature of the system.
Do not glue the tile to the supports, this isn't necessary, and again it would compromise the accessible system.
Walking on a raised access floor is just as sturdy as a solid floor. There should be no rock in the supports - most versions are adjustable so the installer can get them to the exact height. The only caution would be it is a little hazardous walking in stilettos due to the small gaps between the tiles (typically 3-4mm).
What about high wind zones? High wind zones can be an issue - for potentially problematic sites it is best to consult a specialist engineer. In most normal situations as the deck is enclosed there would not be enough wind strength to get underneath the tile and lift it out of place.