I'll again post what I had found this year in the hope of getting these to be reflected in the next update:

Omar Yurtseven's nationality should be Turkish.
Chris Boucher's nationality should be Canadian.
Aleksej Pokusevski of OKC should has 1-year pro experience, instead of 2 years.
Mike James (the FA PG out of Lamar) is missing his 2017 season statline.

Coaches:

Neven Spanija's nationality should be Croatian.
Typos (this is the correct name): Adam Harrington
Donnie Boyce's age should be 48.
Daisuke Yamaguchi's age should be 40, his nationality should be Japanese.

The following have passed and should be removed:
Don Newman, RJ Adelman, Maurice Lucas, Frank Hamblen, Sean Rooks, Paul Westphal

There is a "David Adleman" in the database, guess this is a duplicate and typo of David Adelman IRL

Dean Garrett is an interesting case - he's a former NBA player, but is never involved in coaching after retired IRL. So better take him away from the database.

There is virtually no information on the web about the following FA "coaches". My guess is they were once attached to a D-League team as team trainers/operation staff many years ago and do not worked for pro teams anymore, so suggest to be removed:

Jeff Slogan
Ulrich Morgan
Niel McCaulay
Jason Johnson
Ray Hall
Len North
Johnson Tordelay
Mike Gunny
Mark Castro
Jason Delilo
Bobby Boles
Jamal Williams
Robert Campbell
Dorian James
Peter Smithson
Bob Carswell
Kurt Disher
Rodney Sampson
Peter Kovac
Kenny Kubart

Thank you, I have corrected the errors and removed the duplicates and deceased coaches in the update that will be forthcoming shortly