Hi Marc,
Sorry for the inconvenience caused.
We suggest you to set BlockCharactersOnTextInput to false while using AZERTY keyboard which is missed in our previous sample. Numbers from top row keys can be entered by pressing Shift + number key and minus sign can be entered by simply pressing key 6/minus. We have tested this with v15.1.0.41 in GridNumericColumn and SfNumericTextBox control, both worked as expected from our side. You can download the sample for the same from following link:
Sample:
NumericColumn_AZERTY Please let us know your Essential Studio version if the issue is reproducible with provided sample from your side.
Regards,
Jessie