2 is an anagram (‘muddled’) of GETS ALL with the usual representation of ‘nothing’ put inside (‘entered’). The solution is hyphenated, 3-5, and the ‘initially’ (which is part of the definition) refers to the fact that entries would have been transferred from here to a book.
3 is a double definition, the bit of furniture – also hyphenated 3-5 – having been used originally for a specific card game.