When adding (or editing) a tool to the course, and using a language other than English, saving the link triggers a warning message in the UI telling that the Grade for passing must be numeric.

In some languages the decimal point is replaced by a coma, so the validation should consider the locals.

https://www.dropbox.com/s/qt5k7kqqporr3s6/MDL-50413.PNG?dl=0

The workaround is just to replace the coma with a point