Can someone please tell me what I'm doing wrong?

https://prnt.sc/10jwz3c

The mod believes you intend to get 100% of your production from cracking the oils.

You should have the cracking under the oil processing, this way it will use the excess output in its calculations instead of the refinery. You then adjust the percentage of the refineries to achieve as little excess as possible and the cracking recipes will also adjust accordingly.

https://puu.sh/HoDsx/e0fd3bf7e8.png

Unless you define an input of your own (That is, something below it), then recipes should draw from the excess output of the production line to prevent too much of a byproduct stockpiling. This is also valuable for cyclical recipes that consume and create the same materials, since you don't need the constant demand when it's already available to use elsewhere in the line.

Hopefully that helps explain the process a little bit.

hello there are 2 way to solve your problem
1) Use ctrl+click on heavy oil to set main product on last row
2) change "Computing by element" by "Matrix Solver"

First of all, I would like to thank you for your willingness to help.

@Hellfima I've tried both ways you suggested. However, they do not completely solve the problem.

@Yucie I also tried what you suggested to me. However, I cannot influence what percentage of the machines should work. Therefore, unfortunately, this is not a solution. Or I misunderstood your suggestion.

Here again a screenshot of what I have now changed: https://prnt.sc/10kivi9

@Yucie I also tried what you suggested to me. However, I cannot influence what percentage of the machines should work. Therefore, unfortunately, this is not a solution. Or I misunderstood your suggestion.

Here again a screenshot of what I have now changed: https://prnt.sc/10kivi9

You did a ctrl+click on the heavy oil and that's why it won't work as I had done it. You've otherwise shown you know how to change the percentage, which is 56.5% production if the cracking recipes are at 100%.

I hadn't changed the percentage. That was what the game made of its own.
In addition, the CTRL + click is an attempt from Helfima's suggestions.

Oh, I see. Then I'll explain it a bit more.

You can click the recipe button on the left side to change the production rate for that recipe:

https://puu.sh/HoV6c/246ffc11c3.png

It's here where you can change the entity creating the recipe, alongside adding/removing modules to the entities, including beacon effects. You'll likely be editing all recipes with modules to tweak everything how you prefer, with fine tuning as you become more comfortable with the interface.

I have already tried this way several times. However, the percentage resets immediately as soon as I close the window of the respective recipe. So either I'm really stupid or something doesn't work here that should actually work.

I haven't looked again in Game, because it's 2:15 am and I'm doing everything to go to bed. I can look at it again tomorrow and, if necessary, do a few screenshots of how it will look for me.

I select matrix solver
sometime the solver need more rox to find solution, if you add water that works