Turned out:
In unit EpikTimer I had:
uses
...
Classes, SysUtils, Forms, Controls, Graphics, Dialogs, dateutils;
Where Forms, Controls, Graphics, Dialogs were included for no reason
I removed these dependencies in EpikTimer on my first PC, but on another PC I had a copy of EpikTimer too, where I did not remove these dependencies
I managed to track it down using "Show PPU files" tool