Give us time plzkthx. This is a messageboard where people pop in and post when they have time available. There aren't people sitting around here 24/7 waiting to answer your questions.
Your problem has nothing to do with vectors. You can take vectors completely out of the equation:
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Panel a; // make 2 panels, one 'a' and one 'b'
Panel b;
a = b; // then assign one to the other
If you try that code, you'll get the same error. This is because 'Panel' does not have a usable assignment operator. To be able to do this, you'll need to modify 'Panel' and give it an overloaded assignment operator.