In a 'true' Cucaracha the heel of the supporting foot is not released (except in a forward Cucaracha). This is because the feeling and appearance should be one of the moving foot travelling slightly outside the body, with prssure but without much weight; most weight being maintained on the original supporting foot. If you watched your upper body in a mirror, it should not appear to move far – about a hand width. This enhances the action of the hips and legs.
You could move further, in which case the supporting heel would lift, and you would be dancing a Cuban Rock action. It is fun to play with starting with one action and then changing to the other.
(My first two sentences were in accordance with Walter Laird - accepted Guru of Latin – in his book Technique of Latin Dancing. I happen to agree with him. The rest was my own thoughts)