Can't print the skirt properly

[osterac]

OK,
So I tried to print the temperature tower, but if I print the STL it doesn't print at the right temperatures and when I printed the gcode the filament got jammed. I'll probably get the fans too.
I tried printing a calibration cube, but I noticed that the cube was skewed - it had 2 sides that were square and 2 that weren't (horizontally). Pic attached. It's about .5 to .6mm off, and it's enough so that when I try to print a lego it won't mate with a real lego. I don't know how I could correct this by adjusting steps per mm.
Thanks