If you have apartment number entries that contain a pound sign (#) and you want to parse it as an apartment number while keeping the # character, you can use a special apartment number processing.
By default, the CDP converts all # characters to spaces by the characters control file (charctl.win/unx, located in ./tables/parser_rules). As a result, if the address has the # character, it will be converted to a space before parsing begins. For example, "23 Davis Rd., #C4" becomes "23 Davis Rd., C4". "C4" will still be parsed as the dwelling number, but the dwelling type is a '?' (no type) instead of 'A' (apartment), and the dwelling name will not include the # character.
To process the # character as apartment number correctly, you will need to remove or comment out the # character from the characters control file so that the CDP will recognize the # character as a dwelling type of apartment.
To edit the characters control file