Cannot make a struct that contains arrays as members by Make node without connecting input pin

Cannot make a struct by default values if the struct contains arrays.
Engine version: 4.15.1

1.Define a struct that contains arrays. (With or without setting default values.)
2.Try to make the struct with Utilities/Struct/Make node with input pins are connected. (means using default values)

This causes compile error “pin is invalid” for array input pins.
(Structs whose members are value type only will compile with no problem.)
If default values are set for those arrays, error log looks like this.
> Error The current value (((X=0.000000,Y=0.000000,Z=0.000000))) of the ’ Vertices ’ pin is invalid: Array inputs (like ‘Vertices’) must have an input wired into them (try connecting a MakeArray node).

If want to make one struct, we can use local variables as inputs.
(We cannot use MakeArray node if we want to resize it later, as Resize node cannot resize them…maybe a bug also.)

But when thinking about loops to make structs, no way to make them.
(We need another instance of array but Copy node does not take an array as input. Set node seems to return a copy…but it’s a possible bug I think as Get node returns reference after ver 4.12.)

All I can say is Blueprint’s copy/reference values are kind of a mess.
They should’ve done it like native C++, always pass a reference or pointer to something, never a copy…

Thanks for your reply … but planning a marketplace project, That does not accept C++ one.