In the WAUE_contact_1.php file, line 25:
$WA_MailObject = WAUE_AddAttachment($WA_MailObject,"attachments/".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverDirectory"] ."".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverFileName"] ."");
should be:
$WA_MailObject = WAUE_AddAttachment($WA_MailObject, "".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverDirectory"] ."".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverFileName"] ."");
If you are still having problems, lets make sure the server file name is being set. Change line 25 to:
die("".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverDirectory"] ."".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverFileName"] ."");
$WA_MailObject = WAUE_AddAttachment($WA_MailObject, "".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverDirectory"] ."".$WA_DFP_UploadStatus["WA_UploadResult1"]["serverFileName"] ."");
This will write the server file name and upload folder to the screen, post this value back.