"Column markup" section of the manual simply won't work.

All i'm trying to do is, in order to learn the use of columns, which i need to simulate a newspaper page, reproduce the this code from inside Harlowe's documentation:

|==
This is in the leftmost column, which has a right margin of about 2 letters wide.
    =|||=
This is in the next column, which has margins of 1 letter wide. It is three times as wide as the left column.
 =====||
This is in the right column, which has a right margin of about 5 letters wide. It is twice as wide as the left column.
  |==|
This text is not in columns, but takes up the entire width, as usual.

I'm using a blank project to test this, with no effect. How to use columns? What am i doing wrong?

Thank you very much.