Thanks for the compliments and link Mikko, much appreciated. Reveals several interesting details.
There was a third ex-F1 driver in the field too, namely Keke Rosberg in a Group N Evo VII, he finished 45th.
Aparently Mika said he started off slow on the first day then accelarated as he gained confience. He had to stop and change a wheel at one point, and fell way down the leader board. He recovered to 29th, 12th in class. Not an earth shattering debut by any means. I wonder if he will do any more events?