If the license you purchase in ChartDirector 6.x (that is, at the time of purchase, the ChartDirector version is 6.x), then you can upgrade to ChartDirector 7.x. (From your previous message in this forum, it seems you are using C++. The latest verison of ChartDirector for C++ is 7.0.)
In brief, ChartDirector charts can be transparent just simply using Chart::Transparent as the chart background color. The angular meter examples in ChartDirector all uses transparent background. However, note that MFC may not properly support overlapping transparent controls (that is, the background is not really the window background, but is another control).
I think the issue has been discussed in one of your previous post, and it seems you are in fact using MFC.
We have done extensive research and testing in ChartDirector 7.0 regarding transparency in MFC. We concluded that MFC supports transparent controls over the window background, but not over another control, especially if the controls are moving or updating in realtime. We have tried to use a CDialogEx window configured with a background image using CDialogEx::SetBackgroundImage, and transparency works well in this case.
For MFC, the only reliable way (no flickering or drawing artifacts) for one transparent control to use another control as the background is to combine the two controls into one control. For example, you can override the OnPaint event of the bottom control to include the chart HBITMAP directly onto the bottom control, so you can include the map image directly on the chart.