Extra Items and Level Select:
Open the inventory window by clicking on a Storage House. Then, click 
once on the following items. A red triangle will appear in the item's 
square as each is selected. 

Row 1 - item 3 - wooden boards 
Row 2 - item 2 - iron bars 
Row 2 - item 4 - wine casks 
Row 3 - item 1 - bread 
Row 3 - item 5 - cooked meat 
Row 4 - item 1 - animal hide 
Row 4 - item 5 - plate mail 
Row 5 - item 1 - axes 
Row 5 - item 2 - swords 
Row 5 - item 3 - lances 
Row 5 - item 4 - pikes 
Row 5 - item 5 - long bow 

Then, click on Row 6 - item 1 - crossbow to add 10 of each item to your 
inventory or to complete the current level click on Row 6 - item 2 - horses.