Customisation Unlockables.
     The  following  things are unlocked by colleting the special item
crates in the following levels then beating the level.

Unlockable:                        How to Unlock:

The Astronaut hat                  Collect the special item crate 
                                   in level 1-1 and then beat the level.

The R.I.P. gravestone              Collect the special item crate 
                                   in level 1-2 and then beat the level.

The Creepy speech-bank             Collect the special item crate 
                                   in level 1-3 and then beat the level.

The Insignia flag                  Collect the special item crate 
                                   in level 1-4 and then beat the level.

The Eyeball hat                    Collect the special item crate 
                                   in level 1-5 and then beat the level.

The Alien hat                      Collect the special item crate 
                                   in level 2-1 and then beat the level.

The Post gravestone                Collect the special item crate 
                                   in level 2-2 and then beat the level.

The Captain speech-bank            Collect the special item crate 
                                   in level 2-3 and then beat the level.

The Strong Worm flag               Collect the special item crate 
                                   in level 2-4 and then beat the level.

The Logical speech-bank            Collect the special item crate 
                                   in level 2-5 and then beat the level.

The Helmet hat                     Collect the special item crate 
                                   in level 3-1 and then beat the level.

The Obelisk gravestone             Collect the special item crate 
                                   in level 3-2 and then beat the level.

The Doctor speech-bank             Collect the special item crate 
                                   in level 3-3 and then beat the level.

The Meteor flag                    Collect the special item crate 
                                   in level 3-4 and then beat the level.

The Zap flag                       Collect the special item crate 
                                   in level 3-5 and then beat the level.

The Padded Hat                     Collect the special item crate 
                                   in level 4-1 and then beat the level.

The Digital gravestone             Collect the special item crate 
                                   in level 4-2 and then beat the level.

The Babe speech-bank               Collect the special item crate 
                                   in level 4-3 and then beat the level.

The Crush flag                     Collect the special item crate 
                                   in level 4-4 and then beat the level.

The Petrified gravestone           Collect the special item crate 
                                   in level 4-5 and then beat the level.

The Red hat                        Collect the special item crate 
                                   in level 5-1 and then beat the level.

The Slab gravestone                Collect the special item crate 
                                   in level 5-2 and then beat the level.

The Female Computer speech-bank    Collect the special item crate 
                                   in level 5-3 and then beat the level.

The Tentacle flag                  Collect the special item crate 
                                   in level 5-4 and then beat the level.

The Visor hat                      Collect the special item crate 
                                   in level 5-6 and then beat the level.

The Yellow hat                     Collect the special item crate 
                                   in level 6-1 and then beat the level.

The Cross gravestone               Collect the special item crate 
                                   in level 6-2 and then beat the level.

The Princess speech-bank           Collect the special item crate 
                                   in level 6-3 and then beat the level.

The Bolt flag                      Collect the special item crate 
                                   in level 6-4 and then beat the level.

The Column gravestone              Collect the special item crate 
                                   in level 6-5 and then beat the level.