In the Zulu village, it's lightly raining in every scene with the King standing in front of his hut, but never at any other time.
After Lady Anna twists her ankle, Allan takes of her boot to examine it. In the next scene they're climbing a hill and she appears to be wearing sneakers or white deck shoes with white socks. Further up the hill she's wearing the boots again.
So many inconsistencies concerning date. The letter from the school came bearing stamps of Edward VII who died in May 1910 - that should be definitive. At the pub on first meeting Sir Henry toasts 'The Queen' !!! Hartford accuses Quatermain of confusing the SA National Party (Founded in 1914) with the Nazis (1920-1945). He is being paid in 'pounds' a currency created in 1910 in South Africa !! From here so many items from wartime 'jerry cans' and even words ('yuk') that confuse and post-date this period.
When Lady Anna is in the bath asking Allan to throw her something to cover up, at one point the camera angle reveals that she already has something wrapped around her body, and lingers on it long enough for the viewer to read the owner's name, which is Sharpie'd on one corner.
In the guest house near the beginning (after the bath scene) as they run through the hall way there is an alarm motion sensor on the wall above the door at the end of the corridor.
At 38 minutes into the movie, the four protagonists are seen walking across a field toward notable mountains. In the very next scene, the antagonist is seen walking across the same field away from the very same mountains toward where the protagonists had just come from.