Uso de la tecla TAB en formulario

[jasistemas]

Le pones un nombre de instancia a cada campo (NO NOMBRE DE VARIABLE) sino de instancia (el cuadro de texto de la izq. NO el de la derecha)....

por ejemplo:
fld001
fld002

y en algun frame, le colocas:
fld001.tabIndex = 1
fld002.tabIndex = 2
fld003.tabIndex = 3

etc. esto tambien podrias hacerlo con un ciclo for.
Si quiers que el tabulador pase por un boton o una movie clips, pues con la misma notacion punto puedes asignarle la propiedad.

Dale "tabIndex" en el search de flash y veras la ayuda, entre otras cosas:
Description


Property; lets you customize the tab ordering of objects in a movie. You can set the tabIndex property on a button, movie clip, or text field instance; it is undefined by default.

If any currently displayed object in the Flash movie contains a tabIndex property, automatic tab ordering is disabled, and the tab ordering is calculated from the tabIndex properties of objects in the movie. The custom tab ordering only includes objects that have tabIndex properties.

The tabIndex property must be a positive integer. The objects are ordered according to their tabIndex properties, in ascending order. An object with a tabIndex of 1 precedes an object with tabIndex 2. If two objects have the same tabIndex value, the one that precedes the other in the tab ordering is undefined.

The custom tab ordering defined by the tabIndex property is flat. This means that no attention is paid to the hierarchical relationships of objects in the Flash movie. All objects in the Flash movie with tabIndex properties are placed in the tab order, and the tab order is determined by the order of the tabIndex values. If two objects have the same tabIndex value, the one that goes first is undefined. You shouldn't use the same tabIndex value for multiple objects.