what counts in yahoo as move?
Does it count adding a player to roster or dropping them?
Add / drop one player for another = 1 transaction (aka, move). I believe a "move" is synonomous with the actual acquisition of a player from free agency/waivers. So, if you just drop a player outright, you would not be completing a "move."
It doesn't seem to count trades.
I don't think it counts both.
This appears to be the case, yes.
One of the teams in my league has added 41 players to his roster and dropped 40. I have Maximum player acquisitions for entire season: set to 40 moves.
Do you mean that on the "League" page, under standings, it states this dude has 40 moves? If so, I would be befuddled as well.