Mix is actively supported, although it is no longer available for purchase.
The real power of integrating Mix with Quik! is that you can use your existing data to populate forms automatically. To harness this power Mix needs to know what data to put into which form field. This is accomplished on the Field Mapping screen described in the next section of this document. Before you can start that, however, we need to grab all those form fields from Quik! and put them into Mix.
To do so, head over to the Forms Settings tab > Admin tab. Click the Run Batch button (see screenshot below).
This will kick off an Apex batch job that will, using the Quik! credentials you entered in the previous section, log into Quik! and download all the fields from all the forms you are subscribed to in Quik! and store them in Mix. The batch job usually finishes in about 5 to 10 minutes. To monitor the job progress, go to Setup -> Enter Apex Jobs in the Quick Find box -> click Apex Jobs in the left nav. The Apex Class name of this job is QuikBatchJob (B).
Once the job is complete (C), you are ready to start mapping fields!