I'm not one to really right my own rules, but I wasn't happy with any of the purchased or free Zulu rules out there. So, I created my own and am quite happy with them.
Here are the rules for my custom 10mm Colonial/Zulu rules called, "Assegai to Zulu" (A2Z):
(there are 2 links posted for each file as I'm evaluating which free service is better? But both are for the same document.)
Here is the reference sheet for the "Assegai to Zulu" (A2Z) rules:
If you download them and play them, please let me know what you think of them.