Missing numbers in trial?

Hi, I’m testing out the trial version of Glyphs before deciding to buy… I can’t figure out how to add numbers, as this section under the left ‘categories’ menu is empty, unlike the ‘letter’ section. Is this a limitation in the trial or am I missing something?

Right-click on Decimal Digits, select all the numbers you want in the little window that pops up and click the Generate button.