Darryl Smith, who will be telling his story to commissioners early next year, backed Judge Shaw's appointment but said previous mishaps worried him.
"I hope she's actually learned from those mistakes ... we're only human but she needs to understand that she's dealing with survivors, she's not dealing with a courtroom," he said.
Greg Molony, who sits on the inquiry's Survivors Advisory Group, said he had reservations too.
"She's not a survivor, she is coming from a High Court judicial field, which for me, personally, is a tough role to sit back and watch that happen," he said.
Mr Molony said there was no consultation with the advisory group about Judge Shaw's appointment.
"I don't think we've been involved in that whole process at all and I'd probably have to say we've been pushed to the side ... for the last couple of months," he said.
The Network of Survivors of Abuse in Faith-based Institutions said Judge Shaw was the right person for the job.
Its spokesperson Murray Heasley said survivors in their circle who had had contact with Judge Shaw had found her to be engaging and sympathetic.
"We're confident that any issues that have existed before will be a thing of the past ... particularly in light of the fact that she's now the chair and so she'll be even more cognizant of the need to be just, fair and approachable," he said.
Judge Shaw told RNZ there were fences that needed to be mended to gain the trust of survivors working with the investigation.
She said she wanted to meet with the Survivors Advisory Group as soon as she could.
