Complex sentence: From July 1529 to January 1535, he was nuncio to Spain; from January 1535 to July 1537, he was nuncio residing in Madrid (with Giovanni Guidiccione serving as nuncio before the king); and nuncio to Spain again from July 1537 to March 1541.
Split into simpler sentences: From July 1529 to January 1535, he was nuncio to Spain. He was nuncio to Spain again from July 1537 to March 1541.