On macOS, when exporting from the all devices windows to a CSV file, I get "out of memory" error; and when exporting to an XML, I get "unable to create file Users/username/Desktop/filename.xml" error. In either case, the error message proposes to "press OK to ignore and risk data corruption or press Abort to kill the program", so it is impossible to export.
Thank you for reporting this issue. Are you using WiFi Guard from the AppStore or from our web-site? They are a bit different: the AppStore version runs in a macOS sandbox that may limit its ability to write to external files. Also, what version of macOS are you using?
We have checked WiFi Guard for macOS - AppStore build, and can confirm the issue with exports. It is related to Apple's app sandboxing and how WiFi Guard processes user-selected file names.
We will fix it today, but Apple may take a few days to update the application file in its AppStore.
In the meantime, you can use this simple workaround: add the extension when typing the export file name, i.e. enter filename.xml or filename.csv, not just filename. macOS should then create the file normally.