Hi,
I only have one book that talk about the Re 2002, that's the one printed by Delta Editrice.
According to the above book, the aircraft entered service on December 18, 1942 with 239 Squadriglia, 102nd Gruppo, 5th Stormo as dive bombers.
First action took place on July 10, 1943 when aircraft of 101st and 102nd took-off from Crotone airport to bomb allied shipping.
The above seems to be the only action under the Regia Aeronautica flag because ne next action took place on September 18, 1943 this time with Co-belligerent roundels.
Alberto