When resetting the password, wp-modal login sends an email to the user with a link to reset the password. Following that link gets the user to the wp-login.php password reset page but it has the following message: Sorry, that key has expired. Please try again.
To verify that this occurs with the plugin, I went to the wp-login.php page directly and requested a password reset. The link from the resulting email works without getting the error message.
Other than that I have had no problems and was able to style the modal to follow my site’s theme rather easily.