Pie chart gadget does not display any content with Saved Filters

Pie Chart gagdet on Dasboards does not work at all with Saved Filters in 6.4.11

Create a Saved Filter
Go to Dashboards, Add a gadget, Pie Chart
Select Project or Saved Filter: "your Saved Filter here"
Select any statistic type
Click "Save"

Expected result: pie chart is shown with your selected statistic
Actual result: Nothing happens. Gadget properties stays visible, so does "Save" button

Note: works only if you select a whole Project, but not with any Saved Filters.