What will happen when new members are added to the dimension which is shown in your Panorama chart?
The answer is one of the following:
A. Scroll bar will be added in the bottom side of the chart.
B. The chart will expand itself. If the chart is in a dashboards page, it may ruin the page because the view will extend beyond its area.

That's why Panorama's default setting for "Auto Select all X-axis Members to Chart" (and Y) is false, meaning that the chart won't expand even if new data arrives.

The other side of this default setting can be bad. Last week, we had a situation where one of our dashboard pages acted in a strange way: The page contained two views, where the first view is a crosstab and the second one is a chart. When the user clicked on a row in the first view, it sliced the second view on the desired member in the Y axis. What happened is that after the chart showed two members in the X axis, for example, It didn't show three or four members in the X axis, no matter what. We didn't underatand what went wrong and went home with sad faces on Friday. This morning, we realized that we forgot to enable the Auto-Select setting.