Check through this Phillip Coppens link of megalithic sites of Europe. Something a bit closer to the time frame may turn up. Mainland Europe wold have been an obvious destination but could they have made it as far as north Africa. Maybe they thought to get as far away as possible and some stayed closer others went further a field.
I hope you believe me, Jim, when I tell you that I have been seriously thinking of sending Jean Auel a link to this thread? I assume you know her books.
My english isn't perfect, but I think a writer like she is is able to write a 500 pages thick book about it.
And hey, I know Philip Coppens; I like the guy and his site... he has imagination, but he is also critical and skeptic.