Hi sloopa,
Here is a screenshot from my Qtek9090.
As specci's it works OK.
Could you post your source code so we could try yours to compare it.
The source code where I tested mine, you can find it there:
Elektroschaltplan zeichen
Click on the upper left button for a new sketch, and answer yes to the MessageBox, then you arrive where the Calender control is.
Best regards.