Replicator 2x is destructing its build as it prints

[Sebastian Finke]

also, how do you lower the speed only for one layer?

I expect you use Makerbot Desktop as your slicer? It allows you to set a first layer speed. It actually allows you set different speeds for many steps eg. first layer, outer shell, infill,

i think it has been calibrated when we recieved it, because it wouldnt work before,

You really should recalibrate with every material change. Don't assume that every reel you get is the same.