Problems with Z step Recently I bought a Prusa i3 pro W (from Geeetech) and I've been struggling with something that is ruining all my printings. I attach a photo with what was supposed to be little "boxes":

 

As you can see the Z distance is doing weird things, I think may can be fixed through this configurations, as it seems the Z axis is moving too much:



On the other hand, the form the printer is doing the skirt is also bothering me, I've tried a lot of configurations and I think it's a problem of over extrusion, but I'm a newbie and I don't really know what more could I do...



I'll really thank you for every answer because I've been a lot of days with this and I begin to feel really disappointed with all.. Thank you!
as per base of the pink printout it looks like the bed is far below the nozzle (level the bed)
to check the Z steps/mm setting, the best way will be to home it, then from menu move Z by 50mm and check with a ruler or meter traveled distance.
then using a formula (requestedMove/measuredMove) * currentSteps set new value in to Z steps/mm setting. After that repeat the exercise until you will get no difference.