I'm not certain about that "Calendar/Time Control". I haven't seen anything about it, but perhaps it's a Lotus 5.0 or greater. I'm only useing Lotus Notes 4.6.
If you are too, try placing the date and time in seperate fields, 1 date field, 1 time field- and place them in a Layout region. This pretty much automatically creates the fields as pop-ups.
Check out help on the fields, it will explain more. I don't know off the top of my head the particulars, but for the time, if you want it to be a range (to select start end end times with the same control) then the field needs to have Allow multiple values enabled, and for displaying (under options) set the "Display seperate values with:" property to "Blank Line". Perhaps you need to set the "Seperate values when user enters:" property to Blank line as well- I haven't looked it up lately, but that's exactly how I have one of mine set up.
-MoGryph