Signed up 4 people on 28 June. It's not the friendliest process, but generally pretty straightforward. Got approval emails yesterday. Just about a week, so pretty good.
One of the people is an NRI - Indian passport, living abroad, with a foreign address in the passport. But I just used a Bombay address and it worked.

But no information on exactly how or where to do the final enrollment. The email just says "As a next step, you need to get your biometrics enrolled at Mumbai Airport (or any other designated International Airport in India) during your next international travel."

What I haven't been able to do so far:

• Couldn't apply for a minor though it was supposedly allowed per original notification I believe.
• I haven't been able to figure out how to go about it for someone with OCI. Similar address issues as others have reported. The passport doesn't have an address and the FTI-TTP site needs one, that too clearly an Indian address. MIght try just using an India address. Let's see.

And of course, no response to any emails. Not even an automated eff off copy paste job.