Ciao Konrad,
Welcome to the forum.
I'm not familiar with this specific printer, but it looks like it only has a single black ink. If you use a single color ink your more likely to get a grainier look, but it should make a digital negative. You'll probably get better results using a color. Not familiar with the transparency material either, but as long as the ink does not pool & dries fast.
To find a good blocking color for this printer check out the RNP & HSL arrays
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Micheal has a great website with very good tutorials on how to create your negatives.
ChartThrob would be the way to go along with finding a good blocking color. I used it for my entry into digital negatives and had great success.
I would start with traditional cyanotype as it needs the least density in the negative, is fast to develop and inexpensive to print.
For a first try, just invert a B&W image. Adjust the contrast by eye until it looks like a good negative, print it and then give it a try. If the cyanotype print is a little soft, just crank up the contrast a bit more and try again. Working with images is more fun than test strips. After you've made a few prints, then you can start curving away.