Hi Kim,
Noting that the earliest Lakenheath Flack entry in those transcripts is 1795 I did a quick check in a couple of other parishes to see if that was the earliest for all and found one entry dated 1632. So it looks your Flacks came from other parishes pre 1795, however if you want to continue with Flack research those transcripts could be very useful.
My Flack interest is a bit different to yours, mine is not a blood relative, she is the wife of my maternal grandmother's brother.
Her name is Councellatta Flack, a Romany Gypsy, in 1924 she married my great uncle Arthur Searles in Essex, by 1924 she and her sister, named would you believe Sylvester, had given up the Gypsy life.
My mother met Councellatta and liked her and I and my wife met her daughter in 2004 when we visited the UK. Councellatta and her family are mentioned in the Flack site, I supplied some of that info and one of the site's co-owners, Denise with whom I corresponded, helped me find other info.
Btw keep in mind these are transcripts so there could be further info in the actual PR entries.
Good luck with your research.
