1. Correct
2. No Caution inhibits on a 734.
3. RTO due to 'M/C below V1' - our company SOPs advise once thrust set/~80KIAS, rejection solely due to Master Caution is rarely necessary; only for Eng Fire/Fail/other condition which affects the ability of the aircraft to fly safely. So a M/C below V1 is not an automatic RTO, but decision is left to the crew bearing in mind the safety implications of rejecting at high speed.