Einar,
You can never pass an object property out by reference. This would violate the object encapsulation. For arrays, as you found, you have to acopy() them to a local array first, call the function and acopy() them back.
>1. Using a ParseToArray() function I need to send the array with reference. But I can't use @this.arr, but have to use a local variable @Arr. Is this the way it is?