as if myNewArray[0] contains a reference to myArray. Now to go a bit further i set myArray to null, thinking myNewArray[0] will have a null pointer...NOPE! "1,2,20,4,5" is still in myNewArray[0]
what i can tell you from knowing javascript (ecma bla - the same like ActionScript in Flash5)
1. yes, myNewArray[0] contains a reference to myArray. you initialized it like that.
2. if you set myArray to null, you reset the reference of myArray to "the Array" in memory. but it is still linked to myNewArray[0], so garbage collection will not free the memory.
i never used arrays this way, for compatibility issues i still use the "old fashioned way" described in the Flash4 Manual:
myArray_1_1=...
myArray_1_2=...
and the eval command.