Much of this is outdated and incorrect. We are starting fresh at CasaIndex with information known to be correct - move only information known to be correct from here to there.
Getting source code and buildingCASAInstallFromSource Known to be Erroneous/Deprecated
Several of us beginners found the complete description confusing, so an attempt to go straight to "just tell me what to do to make it work" is ToolBindingQuickStart
Warning: (Wes - original email) if you have options for a parameter and put that parameter in a when block inside a constraints block, make sure you have an entry for each value inside the when block that the parameter could take.