Complex sentence: The main actors at the beginning were Florencia Peña and Nicolás Cabré, Peña decided to resign some time after the genre shift as her character lost importance for the plot, whereas the ones played by Romina Gaetani and Isabel Macedo gained notability.
Split into simpler sentences: The main actors at the beginning were Florencia Peña and Nicolás Cabré. Peña resigned after the genre shift as her character lost importance and the characters played by Romina Gaetani and Isabel Macedo gained notability.