Crossword Maker is a shareware web application to design crosswords in png format. The you can save the png and use it inside your documents or put it on a web or ...

The syntax is simple and powerful. You have to divide every field by ,
Every line has to have the same number of fields.

Write a letter to put the letter in a white square (usally capital letters are used, Crossword Maker can allow you to use also small letters).
e.g. Q,W,E,R,T,Y,

Write a number to put the number in a white square top left.
e.g. 1,2,3,4,

Write a number + a letter to put in a white square the number top left and the letter in the center

e.g. 12L,O,14V,E,

Write a plus + to design a black square
e.g. O,+,77E,A,

Write a blank " " to design a white square
e.g. +, , , ,+, ,