I'll tackle your questions one by one, Dave, and I hope I give clear enough answers. If need be, I'll elaborate.
Effects of Charles' exile: Charles' French exile had many effects on him. One of the most outstanding of them was his court. When Charles arrived from the Continent for his Restoration, he brought along a lot of alien, French finery. His court was worryingly French -- and Catholic! The very fashion Charles brought back with him echoed his stay in Paris. Men wore great big curly wigs, stockings, and high heels. Mirrors, sedan chairs, and all other sorts of continental riches were installed into the English court. One of Charles' later mistresses, Louise de Kérouaille, was sent by Louis XIV and was proclaimed to be a French spy! However, Charles did not only bring fashion and tradition back with him from exile. It was on a much more personal level with him, as well. Almost right away, he favoured Catholicism over the Protestant masses. This makes sense; the very people that gave him shelter when he was on the Continent were Catholics, and earlier, the Scottish Covenanters (a very strict Protestant) had made life miserable for him, forcing him to betray his family and give up his beliefs in some aspects, all to secure his throne. Charles' time in France also made him somewhat of an autocrat; he wanted to rule alone. Louis XIV had absolute power, and Charles I had it for around 11 years. Charles II finally managed to dissolve Parliament in 1681 and ruled on his own for the next and last 4 years of his reign. Charles also seemed to be dependent on his cousin Louis. As aforementioned, Charles made an extremely controversial and extremely Catholic deal with Louis in 1670, the Treaty of Dover. Since Charles had whiled away the English money, and since France had its coffers full of -- albeit French and Catholic -- gold, he soon began to use that French money. Keep in mind that Charles' mother was also French. Charles' time abroad exposed him to different religious, political, and fashion ideas, all of which he brought to England with him. Charles' behaviour was even likened to Louis XIV at one point, proving that Charles seemed to be perhaps mimicking his totalitarian cousin across the Channel.
Living arrangements and people: Charles met a lot of people during his exile. However, I'm not going to start in France. Instead, I'll start after the Battle of Worcester, wherein his army way absolutely crushed by Oliver Cromwell's forces. Charles was in grave danger here, which I'll elaborate on in the next part of this post. Charles first was hidden up an oak tree to escape any immediate danger. No doubt it was absolutely traumatising at the time, but Charles absolutely loved to tell anyone who would listen about this story. His mistresses and courtiers heard it ad nauseum and grew very bored of it. Charles was then stashed away into a succession of priest-holes; tiny holes where Catholic families would stash their priests and unsavoury ecclesiastical relics when the Protestant authorities came looking for any popish activities. Charles reported that this made him very claustrophobic. The holes were extremely tight, and I doubt I could even fit into one comfortably at my height, 5'4. Charles was exactly a foot taller than I, so we can only imagine how awful it was to be stuck in there overnight while you knew your enemies were thick all around. Catholic, Royalist families took care of him as he made his way to France. One remarkable woman that helped bundle him away to France was Jane Lane. When Charles reached Boscobel House, where Jane lived, he was fed, cleaned, and given new clothing. After he rested and was ready to keep on going, she helped him first escape by disguising him. She cut off his long hair to be short, dirtied his hands and face with pitch, and had him ride on her horse with her as the wound their way to safety. Jane would always explain that Charles was her man-servant if they got caught. An extra measure of safety was added, as well. Henry, Viscount Wilmot (Later 1st Earl of Rochester) walked some space ahead and Charles and Jane and was prepared to say that they were out hunting if any Parliamentary forces happened to question them. It's of worth to mention one of his first amours, Lucy Walter, in the mid-1640s. The product of this relationship was James Scott, Duke of Monmouth, who would later rise up in a very scrappy rebellion in an attempt to overthrow and/or kill his uncle, King James II. Monmouth did not have a happy childhood. When Lucy became extremely possessive over Monmouth, Charles and she had a huge falling out, and Charles took his son back. Lucy lapsed into a life of prostitution and died of venereal disease. If I recall correctly, Charles also met Hortense Mancini when he was in France. She was to become one of his most controversial mistresses when she came to England in the 1670s. Charles had several fights with his brother, James, on the Continent, and James was volleyed back and forth between loyalties; to Spain, to France, to his brother.
Was Charles ever in danger?: Yes, Charles was often in danger, especially after Worcester! His first move was to be stashed up an oak tree with one of his generals. Charles fell asleep for most of it (he had that special talent to fall asleep anywhere at any time, even in church), which did put him in danger. As he had his head on William Carlos' lap, William's legs started to go numb and he began to pinch Charles to wake him up, lest he fall from the tree. For a whole day and night was Charles in the tree. Charles told Samuel Pepys in 1680 that Roundhead soldiers passed directly underneath him, but they were looking all around, anywhere but up. That was extremely terrifying and also extremely dangerous. Another instance where Charles was in legitimate danger was when he was riding with his troops. A Roundhead sharp shooter took out Charles' horse from underneath him. The King fell and the horse died, but Charles was for the most part okay, so he got up to jump on a second horse... Which was also shot out from underneath him. Multiple times did he almost die! When he went into town (I can't recall which) to get something, he noticed people were loudly celebrating. When he asked why, someone replied, "Haven't you heard? That rogue Charles Stuart is dead!" There was also a massive bounty on his head, over £1000 in their time, which would be in the millions today, if not more. Anyone who helped him would be executed for treason, but Catholics always tended to see him to safety. Doubtless Charles was still in danger on the Continent, what with all the shifting waves of politics and intrigue.
