The classes imported from ActionScript must be wrapped with the path of the directory where they are saved. This is pre-defined in the class package declaration within your AS code.
Let's say I have a class named Example that is part of the examples package, so the package code inside the class would be:
package examples { //PACOTE DA CLASSE
public class Example {
public function Example() {
//Construtor
}
}
}
And the path of the class in the directory would be raizdoseuswf / examples / Example.as .
To use this class, you need to import it into your project / class using the path and its name at the beginning of the code. See below:
import examples.Example;
var novoExemplo:Example = new Example();
This video can help you a lot.