In the folder where you installed the demo, there must be a subfolder named "playdeck". In it there are some .dck files, in each one there is stored the composition of one of the decks you can use in the demo. If you open one of them with your Notepad, you will see it consists on:

8 lines each one preceeded by ";", of which only the first and sixth ones give information about the deck to the game. In the first you must write (after the ";") the name of the deck, which is the name you must use to save the file. In the sixth one you must write a number for the program to choose an icon to represent you in the game. There is one icon for each color: 24 for green, 6 for black, 16 for blue, 33 for red and 13 for white.

The real composition of the deck, of any number of lines you need; each one of them expressing the name, identification number and quantity of the card. It is written the next way:
.[Card identification number][tab.][No. of copies included in the deck][tab.][Card name]
All written without the [] brackets, replacing in each field its value (which is always the same in the tabulations), respecting the dot at the beginning of each line and with no spaces, except for those included in a card's name.

You can test my decks by extracting the contents of this zip into your "playdeck" folder.
If you would like this page to feature a deck of yours, just send it (click on the mail button in the left menu).