I made another example with 36 instances of one sprite. If you have 36 different sprites or other objects not instances you have to put them in a family. That should work also. I didn't test that.
You can delete the sprites if you put it to a position outside the layout or destroy them.
https://drive.google.com/uc?export=down ... WU5bVhCaHM
The character height and width in the spritefont properties is to define the spritefont itself, not to change the size. If its that what you want you have to use scale.
I don't think it's possible to change the height and width properties with an event. This properties are the real height and width of the spritefont you need that to display it. You can't load a spritefont in an event, so it's not necessary to change this properties with an event.