(DO employee here) It's S3-compatible. Agreed that it's a bit strange in Transmit and other clients to have to first select "S3" when connecting to something el

(DO employee here) It's S3-compatible. Agreed that it's a bit strange in Transmit and other clients to have to first select "S3" when connecting to something else entirely... but that's the world we live in. Spaces isn't working with Transmit 5 yet. I don't have the technical details, but it's a known issue that's being worked on. I'll write a Transmit 5 tutorial as soon as it works.