The north lake was like a "spider long term storage" (sumo was throwing spiders there and they could not move). At some point I was wondering if making some transports and try to get the units back wouldn't make cost but I did not try in long time interaction of water and transports...

Haven't watched the game but I suspect lobster would have been the play, not transports.

any land unit is disabled in its function when below water i think (except melee attack?) 

thank you. if you were right i would agree.. however im sorry but this is not correct.. building/reclaiming/repair and terraform do infact work even when submerged.