Descriptive Problem Summary:
Adding a control at runtime into a pane that has been scrolled, or using winset() to read the control's pos parameter, produces wrong results.

Numbered Steps to Reproduce Problem:

1) Create scrollable pane control
2) Scroll pane control
3) Add control to pane; its position will be further right/down than it should be--it is positioned as if the pane is not currently scrolled.
4) Use winget() to read control's pos parameter; it will return a value left/up from what it should be--as if the pane is not currently scrolled.

Expected Results:
The pos parameter should place new controls, and return the position of existing controls, relative to the logical origin of the pane instead of the physical origin.

Actual Results:
The pos parameter is always calculated relative to the pane's physical origin.