Purge octagon

[e-Mole]

Hi,
How is purge octagon properly used? If I use it, the "tower" is always partially empty (some layers are not printed if in the layer is not material change) ... this is a problem (practically unusable). Where am I making mistake?
Thanks
Tom

[pjr]

On layers where there is no filament change, the tower should still be printed with the filament in use, but as a very sparse layer.

Please slice a model where your issue happens, zip up the G-code file and upload it here.

Thanks

Peter