try using pla, blue tape and no raft.

Hang on 5th gen ? no heated plate. So you are using pla.

So basically blue tape, better calibration and no raft.
Blue tape is blue painters tape: http://www.amazon.com/Scotch-1369894...+painters+tape
I use duck brand but the 3m should be just as good.
Pla sticks to it like hot toffee to skin :-)
And if you've never burnt yourself making toffee - it's an experience to look forward too - not !

I've never needed a raft with pla. And I'm basically using a makerbot 2nd gen copy :-)
Mind you from what I've heard about the 5th gen - I wouldn't swap my cheapo flashforge clone for your spanky expensive machine either :-)
But blue tape and no raft should fix the problem.