Always happy to answer the Captain's questions
Q1. Some one with a spear can throw it. Is it assumed to begone or do you have more than one? Same for throwing knives etc.
A1. It is gone.
Q2. Spears say they need 2 hands which mean they could not be used with shields, Zulu style. I assume this is a mistake?
A2. No it isn't a mistake, but then you haven't seen the Zulu list yet have you
For the time being consider the Assegai to be used like a sword, so count it as a sword.
Q3. If you pay for mystical skills are they one use only or can you cast them every turn?
A3. A Mystical Power can be used once per turn in the appropriate phase.