Base the columns values on an other (custom) picklistfield

At the moment the columns are solely based on the field System.State.
In some cases it could be handy that you can use an other field.

It should be based on a text picklistfield (for safety reasons, do not use other system fields) like custom fields.
The check on a state change should be skipped.

Note: Not all workitem types will have this (custom) field... so this has to be checked first.