A BMX bike isn't intended for velodrome racing no matter how you parse the language. Yet, they're sold without meeting some of the CPSC regulations.
I sent an email to the contact person of CPSC bicycle regulations several days ago asking a direct question about lack of full-length or even a circular chain guard on fixies and single-speed road non-cruiser bikes. So far, no reply. Probably never will get one. The saying seems to apply "turn a blind eye".
The question in my mind regarding this ultra-compact folder is, does it have "one rear sprocket" or 3 rear sprockets (two on the jackshaft and one on the rear hub). Sheldon Brown's bike glossary calls the toothed wheels that the belt runs around a "pulley" not a "sprocket" but the Gates Carbon Drive website calls them sprockets, so what are they as far as CPSC goes? Probably sprockets. So the bike in question has 4 sprockets total. Is it exempt?