It can be used in order to import an existing QtiPlot .qti project file. If your project has been saved in a compressed format, you must select the .qti.gz file format.
This dialog can also be used to open files created with other software like OriginLab (.opj and .opju, only on Windows operating systems), Excel (.xls, .xlsx) or LibreOffice (.ods, .fods).
The Name and Path input lines can be edited manually and provide completion. The push buttons next to these input fields open a file dialog allowing to select the file name or the path to its parent folder, respectively.
If the New Folder box is checked, the file is appended as a new folder into the current folder of the project. The newly created folder becomes the current folder.