For more control over the date-time x-axis and formatting I suggest to take a look at the TMS FNC Chart (http://www.tmssoftware.com/site/tmsfncchart.asp). We have redesigned this component from scratch, taking all feedback from the TMS VCL Chart into account.
There are some shortcomings regarding Datetime X-Axis and XY-Charts in the TMS VCL Chart, which we have completely rewritten in the TMS FNC Chart, please contact us directly in case you decide to move to TMS FNC Chart.
In the above case, you also need to set the StartDate, from which you want to start inserting dates: AdvChartView1.Range.StartDate
Perhaps you can send us your sample, so we can see what is going wrong here, and modify the code to have the datetime ranging work for the TMS VCL Chart. If there is anything you might need extra in configuring, you can afterwards migrate to TMS FNC Chart if necessary.
I was using ctLine. I switched to ctXYLine and the dates now display correctly! Excellent.
I have horizontal scrollbars checked but no scrollbar appears. I can move through the chart horizontally by holding down the mouse button and dragging, but it would be better if there was a scrollbar as more and more data points will be added as time progresses.
The horizontal scroll option is only available for dragging the mouse. There is no separate real TScrollBar enabled. You can however enable the navigator, which is a scrollbar like option within the chart itself.