Per Kathy Derkin, in BRC (HPC) ticket 357 on 2015-06-15:
Step 3 uses awkward language, "Download the profile to your computer, smartphone, or tablet. Once you've created your Pledge profile via the web page, you'll need to download it directly onto your device". There is nothing to download at this step. The Pledge program is downloaded and installed at Step 1. At Step 3, I am inputting the Profile data generated in Step 2.
When I mentioned that (at least per my mental model), a Pledge profile is downloaded in the background to one's device, Kathy pointed out:
Regarding point 4, I see now what is meant by downloading in that context. From the user experience though, I would characterize it is a data input step enabling the authorization of Pledge on that device.