It is best advised to do an incremental upgrade. If you really have a project from version 6, then you should upgrade to 7.1.xx and then 8.0.xxxx. It is a big change from that version and it is not guaranteed that it will be completely successful. To get a copy of OpenSpan 7.1, you will need to open a Support Request for the version that you need 7.1.xx. Then you can get Pega Robotics 8.0 from Digital Delivery.