Here is a list I hope is complete of the riddles that can be posed by the ghost of the navigator in Satnajoskull, so that you only have to identify them with the first few words, then look for the numbers.

Let's start with those which really are riddles, with an answer that is not purely calculation: - "We are very large...": This one is about Ursa Major/Minor, which are made of 7 stars each. (ASCII: •) - "Most of them are men...": This one is about chess, 32 pieces. (ASCII: sp)

Now the other ones, in which you just have to sum/substract the numbers: - "One knight...": 1 (the knight, 1° line) + lands (2° line) - "One Buccaneer challenges his rivals...": 1 (the Buccaneer, 1° line) + rivals (2° line) + guards (3° line) - those who are caught (4° line) - "For days we sail across...": 7 (the seas, 1° line) + islands (3° line) - "X Pirates are sitting at a bar...": pirates (1° line)+ beers + rum (both on 2° line) + number of those asking for gin (3° line) - left beers (4° line) - "Vast schools of fishes...": caught fishes (3° line) - fishes which escape (4° line) -"X Bottles full of whiskey...": bottles (1° line) + 1 (the burglar, 2° line) - "One man awaits...": 1 (the man, 1° line) + people on train (2° line) - people exiting (3° line) + people waiting (4° line) -"Count the changes...": days (2° line) + more days (3° line)

What can also be useful is to remember that ascii from 48 to 59 (both included) are numbers from 0 to 9. If you got an ascii "n" in that range, just calculate n-48 to get the corresponding character.

Hope it helped!