If you create the following Glamour browser:

tabulator := GLMTabulator new.

tabulator column: #one; column: #two; column: #three.

tabulator transmit to: #one; andShow: [ :composite |

composite fastList display: [ :x | Array with: x ] ].

tabulator transmit to: #two; andShow: [ :composite |

composite fastList display: [ :x | Array with: 2 * x ] ].

tabulator transmit from: #one; to: #three; andShow: [ :a |

a fastList display: [ :x | Array with: x ] ].

tabulator transmit from: #two; to: #three; andShow: [ :a |

a fastList display: [ :x | Array with: x ] ].

tabulator openOn: 4.

You will get the following browser:

if you then select 4, the third list appears. If you then select 8, the value is changed:

But since then, the third list does not change. It stays with 8 value forever.

Do I miss something? Should I define it differently?

Or if it is a bug: Can you give me insights how to fix it?

Tested in the latest Pharo 6.