Heroquest UK version differences - 1989 1st edition to 1990 2nd printing, detailed changes compared

About HeroQuest, from BoardGameGeek:

HeroQuest is a Dungeons & Dragons-style adventure game. One player acts as game master, revealing the maze-like dungeon piecemeal as the players wander. Other players take on a character (wizard, elf, dwarf, or barbarian) and venture forth into dungeons on fantasy quests. The HeroQuest series consists of the main game and a number of expansions. The game is played on a grid representing the interior of a dungeon or castle, with walls segmenting the grid into rooms and corridors. One player assumes the role of the evil wizard character (Zargon/Morcar), and uses a map taken from the game's quest book to determine how the quest is to be played. The map details the placement of monsters, artifacts, and doors, as well as the overall quest the other players are embarking upon. During a Hero's turn, the player can move before or after performing one of the following actions: attack, cast a spell, search for traps and secret doors, search for treasure. The game ends when every player has either returned to the spiral staircase, exited by a door, or been killed by the evil wizard. If the objective of the quest has not been accomplished then the evil wizard character wins. Items collected during the quest may be kept for future quests. The quests usually form part of a longer story, especially the quests which are part of the expansion packs. Additional material, which is generally missed since it is not technically an expansion, was published in the HeroQuest: Adventure Design Kit which did feature one more Heroquest adventure: A Plague of Zombies.