Spoiler alert!
These are the answers to the Nexus puzzles
nxa001: They can all be preceded by SUN, or by MOON
nxa002b: They are all anagrams of boys names: Sean, Karl, Stan and Eric
nxa003: The can all have LIGHT as a suffix
nxa004: The can all be preceded by SUN or end with LIGHT
nxa005: They are all fish
nxa006: The are all English towns/cities