Hi, Love your plugin. It's just what we needed.
OK, signed up for an Authorize.net test account, set up the form, tested it...
The transaction goes through and even gets sent to my sandbox developer account... email gets sent to me, and I'm taken to the thank you page but on the top it throws this error.
Warning: nl2br() expects parameter 1 to be string, array given in /home/mysite/public_html/wp-content/plugins/gravityforms/common.php on line 3859
It also throws that same error when I look at the "entries" page in the form submission area from the WP backend.
Any ideas how to fix this?