Jon and the others,
Imagine I am to depict routinely series of recorded points by means of a
user defined chart, where one chart series are the mentioned points, and
another one is a user defined regression function. As I do not intend to
stuff numerous sheets in a workbook with excessive charts, I would prefer
macro that is able to present, promptly and temporarily, a neatly formatted
user chart, fed with actual values. When using usual commands

Charts.Add
ActiveChart.ApplyCustomType ChartType:=xlUserDefined, TypeName:= . . .

the conflict, however, comes in:

ActiveChart.SetSourceData Source:= . . .

Assigning a simple (double-)block for the first of the series is trivial
here. But the second series, though primarily contained in the template
chart, virtually disappears and thus cannot be declared by a following
..SeriesCollection(2). It requires adding the second Series, with necessary
loss of original format.
An idea arises that - if the Source:= could be declared as to comprise both
of data series by some sort of Range combinations or so - the problem would
be solved. Has somebody sought such a solution?
As a remark, my way out now is copying the template chart from a workbook
with getting data from the actual worksheet. But still I succumbed to a
temptation to seek a smart idea.
Sorry for my submitting marginal topics.

Petr