Was there any controversy surrounding the choice to portray Othello in black face? Did any prominent civil rights leaders criticize the choice to use a white actor in black face for the lead protagonist or was the decision to use Laurence Olivier well received by the civil rights community?
I've personally only read Olivier's take on the 1964 production/film, so my answer is somewhat tangential. However, I do believe that it is important to distinguish between dark makeup and "blackface." While the two terms have largely merged in critical discourse today (and for good reason), they would have been understood as separate phenomena at the time.
"Blackface" refers to a specific type of makeup that originated in minstrel shows, and was designed to lampoon stereotypical features of African-Americans. This is the makeup of Al Jolson, Amos & Andy, and so on. Blackface makeup left a large white area around the mouth to signal oversize lips, again a nod to racist stereotypes. Blackface/minstrel performance usually also included costuming that was exaggerated; large bow ties, overlarge suit collars and so on. Voice and movement were likewise altered to lampoon African-American stereotypes.
Here is an example of two performers in 1950 applying blackface makeup and slipping into stereotypical "blackface" personae.
As for Olivier, in his mind (and the minds of those directly around him), this wasn't blackface in the minstrelsy sense. It was him made up as an African. His intention was to play Othello, not to lampoon or send-up. In both of his autobiographies he discusses the process of the production and film to greater or lesser degree, and he does not ever hint at any agenda other than disappearing entirely into the character.
As the Civil Rights movement in the US (and Postcolonial/Critical Race Theory around the world) advanced, most began to see this as a distinction without a difference, since the actor donning makeup like Olivier's is still assuming a cultural background, representative burden, and personal history that cannot (like many other aspects of characterization in theatre) be learned in rehearsal. Furthermore, the casting of a white man in a role like Othello further decreases the number of available roles for actors of color (and there aren't that many to begin with).
In sum, in Olivier's cultural and historical context, this wasn't "blackface," nor was it disrespectful. We have reason to see it as such now, but he wasn't working from the same operating assumptions.
Olivier's autobiographies: