To make lime green with paint you take the base colour GREEN and mix it with white! Or you can buy lime green paint, junior! :P
Yes, you can.
Absolutely not and you should use the same manufacturer of the paint you have on there also. Sorry you can only use a chlorinated rubber base paint on a rubber base paint. If you try to paint with the chlorinated rubber base on top of a synthetic rubber base paint it will probably peel like a bad sunburn.
What they call "oil base paint" is really called "alkyd base paint." So yes, you can do that.
Most enamels will work just fine. (make sure the base has been sanded with fine sandpaper to give the surface some tooth for the paint to adhere to)
Yes, you can
If the base coat used in your project is water base then yes, you bet you can. If there is any chance that the base coat used was an oil base paint then you cannot paint directly over it. The acrylic enamel will not adhere to the oil base paint and will begin to peel off as soon as it is dry. In which case a coat of primer is in order.
Yes, you can. You can always paint over with same paint.
Paint is a base.
Yes, as long as you have the same base that's not a problem.
Don't mix them, your inviting trouble
The best base paint to use before you paint your walls the color you want would be a water base paint since some people are allergic to latex. Also, a water base paint can be removed easier and doesn't interfere with the color you will be adding over it.