The correct answers to these open questions are the following.
1.- How was the world transformed during the First Global Age?.
The world was seriously transformed during the so-called First Global Age that started approximately in 1450 and ended by the 1770s. During these 350 years, the world passed from an era of exploration and conquer by the European monarchies that were ambitious and wanted more richness and territories to increase their power and control in Europe, to a time of conquering and colonization of these new territories, as was the case of the North American territory and Mesoamerica.
After this period of dark ages during the Middle Age, the Renaissance represented a great "jump" to humanism and the reappearance of the arts such as painting, sculpture, and architecture. Then it came the wonderful times of the Scientific Revolution and the Enlightenment, which really changed the way people lived for all the discoveries and new concepts in the form of governments, liberties, citizens, rights, and social contracts.
It was the time of brilliant thinkers and philosophers such as Voltaire, John Locke, Baron of Montesquiou, Jean-Jaques Rosseau, and Thomas Hobbes.
2.- The effect that nationalism had on Europe during this century of the 1800s was that nationalistic ideas created many problems and confrontations in Europe due to racial differences, ethnic confrontations, territorial expansions, and the imposition of the will of the Emperors over other territories. The strong sense of attachment or belonging to one’s own country made people fight against other tribes and nations and Europe lived bloody times of wars and conquest.