Re some of the issues raised, whilst apparently solved for Shedrus, others may have similar situations.
Re minutes, the problem of having them changed before the meeting is copies of the minutes would have been distributed after the relevant meeting, and you cannot control accurate amendment of each copy issued.
A better way is normally at the start of AGM, EGM, SC meetings, there is a motion to accept the previous minutes. If they are in error, one normally draws attention to the error, and if agreed by those who attended the previous meeting, the amendment is written into the minutes of the current meeting by the secretary.
Re by-laws affecting common property, one Section of the Act is particularly relevant is 149, which allows the OC to go to the tribunal to get a by-law registered even when the concerned owner refuses consent for the by-law.
Also, re air conditioner compressors, most councils use the state rule that limits wall hung units to max height 1.8 m above ground
refer link https://www.legislation.nsw.gov.au/#/view/EPI/2008/572/part2/div1/subdiv3