Anyway, I think that when the goal is reached, you can't withdraw your pledge when it makes the project to go below its goal.
Where'd you get that idea? I'm not saying it's unavoidably false, but if it's true, then it's a pretty fucked up system. Say I wanted to pledge a little but accidentally pushed the zero button one too many times. Does this mean I now have three choices:
A: Contact Kickstarter and ask me to remove the pledge I just made
B: Kill my credit card so that the payment cannot go through
C: Pay the money and suffer the consequences and financial problems?
Don't quote me on this because I'm not the expert of Kickstarter and I don't claim to be one, but I think you can withdraw your pledge just like any other fellow before you, if you decide you didn't like the project after all, or if you made an error while inputting the number of dollars you wish to pledge (and like the dimwit you are, skipped all the confirmation messages, I mean there are only like four of them during the process)