Just to clarify re voting on special resolutions – for such a resolution to pass, there must be no more than 25% of the votes based on unit entitlements cast against the resolution. Otherwise the resolution is not passed.
An abstention is a non-vote, it is someone choosing not to vote. It is not an indication of support for anything. If you vote informally in an election you are doing the same thing, you are choosing not to exercise your vote.
It is very common for strata managers to chair meetings, ours does which is fine because he knows what he is doing. If anyone is chairing a meeting and there is a resolution in which they have an interest, they should step aside for consideration of that motion.