@pedro
It’s not so much the keyboard settings, but the ‘locale’ used when SketchUp was installed.
Type or copy+paste + [enter] this in the Ruby Console:
Sketchup.get_locale.upcase
If it’s an EN-US or similar locale you use a ‘.’ as the decimal separator and a ‘,’ as the files separator thus::
12.3,45
or if you want to use units other that the model’s current units settings:
12.3m,45m
Remember NOT to click in the Measurements box, just type what you desire…
And remember to press Enter when you are done with the input.
BUT, if you have a ‘European’ type of locale then you might have the decimal separator set as a ‘,’ and the field separator then becomes a ‘;’, so it’s now:
12,3;45
or
12,3m;45m
Does that help ?