Ok, it’s been a while since I had the time to write something… Meanwhile, quite some progress with the enlarger. After ordering some 30×40 multigrade paper I learned that you need some special filters. Papers have apparently a default gradation (2 for the Adox EasyPrint), but this might not be what you want.
However, the internet haz it! it is posssible to develop multigrade paper by using a multigrade head… or a color head. With the color head you can change the layer / gradation of the paper by using the yellow and magenta filters. The more yellow the solfter, the more magenta the harder (5) the paper gets.
By a lucky coincidence I found a rather cheap Kaiser System-V Color Professional head. The guy selling this provided me as well a sheet containing the filter values for the gradation:

After solving the gradation problem I had to exchange the trays… 30x40cm is quite big, so I bought new trays – the cheapest I could find. My first try to get simply some cheap plastic boxes from OBI (Home Depot thing) didn’t worked out.
The results were very rewarding, and it’s such a fun. Not only the analog photography itself, but as well the post processing, and the paper prints.
Next project is to be able to develop color film. Chemistry is finally again available, so I will try this out!