Hello o/ , I finally set up my paypal to get the IPN, and i test it in anonymous mode and the module it's working fine( awsome ), but now when new account's need to be aprove/deny/active i get this error. How i fix it?

Sorry i don't know what happend with the image code but here is:

Little confused. Is this a user registration or a donations issue? The title says Donations, but what your saying in the post is for registration.

The error there to me looks to be a mis configuration on your site. Make sure you have in both

ACP -> Preferences -> General Site Info -> Administrator Email

and

ACP - Forums ACP -> General Admin -> Configuration -> Email Settings -> Admin Email Address

as the same email. Also, in the forums, make sure you don't have SMTP Server Address set to yes unless you are using SMTP.
Other than that, if that is all good, can you look in the root of your site and see if there is a error.log file. If so, Delete it and try registering to reproduce that error and attach the error log to a post here.

I'm sorry, you're right, i was installing the module on my test site, but now you remember this things and it's ok, i also already install it in the official site and it's working too, Thank you!  

So, is everything good now? No error anymore?

Yep, everything good now, thanks

Glad to hear.