The website tells me downloads are granted on  "invite only". I left my email adress to be selected for an invite but I'm not a developper, I'm just joe bloggs becoming more interested in BTC by the day, doing a BTC course with #sayloracademy and trying to do things right with NOSTR. I think the option to create your keys with your coldcard is awesome, it's really empowering. I looked at the other ways to do it but they are pretty involved technically, you have to be pretty computer savy which I'm not.