I have a fix for the initial question:
Replace the following in wpgft-loader.php line 390 and wpgft_processOrder.php line 314
if( function_exists('wp_nonce_field') ) $formCode .= wp_nonce_field($nonceID);
with
if( function_exists('wp_nonce_field') ) $post_content .= wp_nonce_field($nonceID, "_wpnonce", true, false);
This will prevent the <input> field from being output before the <!DOCTYPE