Hi - I’m not seeing that here when I do the following:
I open your file and see 3 text objects in the viewport. They are all using the style called “Default”. This style is using a font that I don’t have on my Mac. In Document Properties, I make a copy of the “Default” style and it gets called “Default 01”. I change the font to “Comic Sans MS” and the height to 16. I then select one of the text objects in the viewport, click on the Style drop-down in the Properties panel and change that from “Default” to “Default 01”. At this point, the text object in the viewport is changed: the font is clearly Comic Sans and the height is clearly bigger than it was before.
Hi @miano, I confirm that it is working here as expected, no problem changing styles but, as Wim, I don’t have that font either, so Rhino automatically changed to Arial. Have you tried with a different font? maybe the problem is just with that specific font you are using…