Catherine Oxenberg and Mark Vicente were some of the first to comment.
Raniere declared he's "innocent" just days before his sentencing.
"What I thought I was learning was self-help and personal growth," she said of the group, which has been called a cult by some.
"These supporters of Mr. Raniere asked me to sign a petition," Knox explained in an email to an Albany publication. "I personally do not know enough about the case to make any judgments about whether his conviction is wrongful or not."
Tom Welling, Michael Rosenbaum and Allison Mack starred together in the show "Smallville" from 2001 to 2011.
A former NXIVM "slave" accused 'Smallville' actor Allison Mack of forcing members of Keith Raniere's secret sex cult to follow extreme diets for more than a year.
A woman took the stand and alleged "Smallville" actor Allison Mack invited her to an NXIVM group meeting where someone forcibly performed oral sex on her while she was blindfolded.
Along with Salinas, Clare Bronfman, the heiress to Seagrams liquor, was included in the graphic presented in court.
Lawyers for Raniere reportedly wrote that the texts about owning a "slave ... that you could groom, and use as a tool" were taken out of context.
Stone, who worked for Trump until a rancorous split in 2015, was once on the group's payroll.
Mack allegedly preyed on vulnerable women using a tactic described as "love bombing."
A whistleblower for the group told Newsweek that Mack was "deeply influenced" by charismatic leader Keith Raniere.
Keith Raniere is alleged to have created a secret society in which he blackmailed "slaves" and branded them with his initials.