Update Project

Thank you for your previous answers by the way.
I have 2 mores questions:

1st question:
Once a project is validated and published, the author project (user) cannot do any changes.
Indeed, if the user want to change the amount of his goal, the date, maybe he needs less money or more, changes cannot be done. PLease advise.

2nd question:
Are you developing a solution with Merchant account such as Authorizenet, Ogone, etc???

Thank you for your prompt reply, especially on the 1st one.
thank you