You shouldn't have encountered an issue with a 502 unless it was during the window of time where our front end deploy failed.
Unfortunately, we only support NPA-NXX-XXXX numbers for sign up at this time. If you contact us directly at support@telo.com, we can provision you an account if you are still interested. We plan on offering international coverage outside of the NANPA / NPA-NXX-XXXX dial plan by the end of the year.