Yes, you can try making the glyph in Trial mode, but you cannot save the font.
However, you can test the font with the new ligature in your program by displaying the font in the Font Test window in FontCreator, then switching to your program and select the temporary font that FontCreator makes — “FC Test Font nnnnn”
There are two ways to add ligatures to fonts:
- Create the extra glyph (character), and assign it to an used character that is convenient for the user to type, e.g. #.
- Create the extra glyph, then add an OpenType glyph substitution, so that if the user types 1 then 0, the new ligature is substituted for the pair. This requires a program that supports OpenType glyph substitution. Not many do.
How much it costs depends on whether this font is for your own personal use or to be used commercially. Pricing. If its just a one-off job it would be cheaper to use an online font service like Your Fonts
