To answer this question you just really need to understand the Properties of Propane. I inserted a link for you to look at below but the basics are this.
1. Propane remains a liquid if it is enclosed in a sealed container strong enough to withstand the pressure generated as it tries to return to a gaseous state.
2. Propane boils at -44 degrees F. So basically at -44 you can carry it around in a pail. At -43 and warmer it will turn to a gas/vapour with the pressure increasing as it gets warmer if it is in a sealed container.
3. The warmer the temperature the higher the pressure. At -44 it is 0 PSI. At 100 F it is 172 PSI.
4. Liquid expands 270 times as it turns to a vapour.
5. Releasing it to atmosphere will cause it to vapourize. This will react like AC materials drawing heat from the surrounding area when it vapourizes.
6. Any injector will control propane keeping in mind that some materials (seals) can be affected by the fuel. Depending on design the possibility exists that the tip may frost up as the liquid is released and expands sucking heat out of the metals around the area to vapourize.
7. The diesel injector will work depending on what heat value you want to achieve.
8. The value will change with temperature because the tank pressure will change.
9. The value can remain constant if the pressure is controlled with a delivery pump and a return line with a regulator on it that returns excess fuel to the tank.
10. An ECU is required to pulse the injector in most cases.
11. Heat may be required to keep an injector from freezing up (icing up at the outlet tip).
http://www.propane101.com/aboutpropane.htm
Ask some more specific questions and I or another member may be able to answer them but first do all you can to educate yourself on the basic properties.