In short, be suspicious of anything colored red and less suspicious of anything colored blue. The red stuff requires some kind of intervention.
Direct translations are colored blue. They are a part of the current dictionary and can be edited or deleted.
Suggestions are colored red. They are indirect translations from other dictionaries. They are not part of the current dictionary and thus cannot be edited or deleted. They can only be accepted or hidden. Good indirect translations should be accepted in the edit page. Silly indirect translations can be hidden by submitting a suitable translation for them. (If X has a silly indirect translation Y, we can hide it by translating Y with Z.) Terrible indirect translations can be deleted by finding their source in other dictionaries and fixing it. Terrible indirect translations are usually caused by homonyms or vandalism.
Stubs are words that don't have a translation in the current dictionary.
Ideally, only synonyms, hypernyms and hyponyms should appear in the related words list. Unrelated words in the related words list are usually caused by homonyms or vandalism.
Translations are ordered by their rank. Rank is displayed as a superscripted number next to the word. Higher rank on the left side means that the word has more translations. Higher rank on the right side means that the translation is attested by more indirect translations.
Note that the ranking rules are not perfect and will be changed soon.
Ideally, the words should contain qualifiers for part-of-speech. Some of the tags are listed in the guidelines.
Different senses of a word are marked by a synonym, a hypernym or an object in parentheses.