I sang my version (below, learned from my father but also sung in the Scouts - invented by Baden Powell) to Prince Mposi Mamba of the Swazi people, and asked if the first lines were in any way rude. He said, "No, it just says that a warrior should be brave".

I ziga zumba zumba zumba
I ziga zumba zumba zay

Hold im down, you Swazi warrior
Hold im down, you Zulu chief CHIEF CHIEF

For we're marching on to Laffamsmere
To Laffamsmere, to Laffamsmere
For we're marching on to Laffamsmere
Where they can't tell sugar from - tissue paper, tissue paper, marmalade or jam.

I saw a little boy sitting by the fire

I saw a little boy playing with his wire

[Plus I think the dinghy bit above - which I had forgot!]