I had to abandon the map. The last update doubled the reload time of Meltdowns If cooled with water, i die instantly, even with pause-building there is no way i can supply my Meltdowns with Cryofluid. But thanks for your Help :-)
oh and i was building Units allready, but No effect. The Titan Mechs kill a Meltdown with 4-5 Hits, any Minion i produce dies in one Shot.