User blog:CrimsonWarden/Time Stop and Time Stop Countermeasures

Details first:

Within the Overlord storyline, Ainz in the only one who is mentioned to possess, make-use of and has a proper bearing of Time-Stop magic. The instances in the NW where he used Time-Stop magic was with his battle against Foresight, and his duel with Gazef. He had also repeatedly mentioned to having countermeasures against Time-Stop magic but no else has any magic of that nature in the NW.

Questions:

Why didn't Ainz use Time-stop in his battle against Shalltear? Did the members of AOG place Time-Stop countermeasures in  Nazarick? Did they equip the guardians with items that counter or neutralize Time-stop magic?