Conversation so far:
What was Charles Taze Russell accused of doing?
He was accused of immoral conduct including mental cruelty, referring to forced celibacy and frequent cold, indifferent treatment.
Who did Charles Taze Russell subject to cruelty?
It was alleged that he subjected his wife Maria Frances Ackley to cruelty.
Who made the immoral conduct allegations against Charles Taze Russell?
Maria Russell filed for divorce under the claim of mental cruelty.
Were the allegations of cruelty by Charles Taze Russell to Maria Russell true?
Did maria Russell do anything apart from making the immoral conduct allegations?
Maria Russell filed for divorce under the claim of mental cruelty.
Was Maria Russell granted her divorce request?
She was granted a separation, with alimony, in 1908.
What other immoral conduct was Charles Taze Russell accused of besides cruelty?
During the trial Mrs. Russell's attorney alleged that in 1894 Mr. Russell had engaged in improper intimacy with Rose Ball, by then a 25-year-old woman.

Question: what more is known about this allegation?
Self-contained rewrite: What more is known about Charles Taze Russell's “improper intimacy” allegation besides the name and age of the woman he was intimate with?