We don't know if evil is relative, but you can follow the dilemma with different wording.
We don't like our wellbeing and our ability to make our own decisions taken away from us. We suffer, which is something we want to avoid in general terms. It goes beyond humanity, as many animals also seem to seek the satisfaction of their will (being it playing, feeding, instinctively reproducing, etc.) and seem adverse to harm and to losing their life.
So... If we are such creatures, it's natural we don't like situations and beings that go against this. We don't like volcanic eruptions when they're happening with us close the crater. We don't like lions or bears attacking us. We especially don't like other humans harming us as we suspect they could have done otherwise in many cases. We simply don't like these things because of our 'programming' or 'design'.
Problem? There are a few. The first is God asks us to like him when he's admitting that he is actively doing the things we dislike almost universally as human beings. That makes us fall into internal conflict and also into conceptual dilemmas. Perhaps due to our limitations, but nonetheless real and unsolvable to us.
Then you can argue that the way we are is designed by him, so why design something that is going to live, feel, think certain things as undesirable and then impose such things unto them? Let's say I cannot say that's evil, I at least can say it's impractical as it will certainly cause trouble to his mission of accepting him (and following him). If that obstacle for us is part of the plan, that's not for me to say, yet it is an obstacle in our view and experience. In human terms, all this might be classified as unfair or sadistic*, which is the reasoning in the guide and how you can follow it in this perhaps closer way.
Now, about this last part, while we can argue that *those terms arise from our own dispositions and might be different to other dispositions (aliens that do not experience pain, for example), is that enough to invalidate our perspective? Then what's the place of empathy, which I am assuming is also a part of God's gifts to us? What's the place of compassion, as written in many religious texts of supposedly divine inspiration? If we need to carry our dispreference, displeasure, dislikeness—suffering—and not to classify it as necessarily evil when the gods impose it to us (as it is our judgment only), then why classify it as evil in other circumstances?
I hope I am getting my new point though. What this all seems to conclude is that if the lack of respect for the suffering of the animal kingdom is not worthy of being classified as bad (for whatever reason, here I argued that because this comes to be only by our characteristics/disposition); if, therefore, we cannot say a god is evil for going against our wellbeing and against our ability to make our own decisions, then I fail to understand many other things that tend to follow religious thinking and even moral thinking.
This might sound pedantic, but it isn't, it was actually naive: I expected a better environment in academia when I was young.
Why? Because academia is supposedly full of bright people, and I assumed they would be bright enough to be cooperative (because academia advances more when we are, and they supposedly love knowledge); unattached from superficiality (like judging people by their looks, money, etc., because they should know an interesting person can come in any "package"); relatively ethical (as bright people should figure out something close to the categorical imperative, although with unique details); a non-dogmatic, eager to learn and correct their ideas —over preferring recognition and pettiness— attitude (again, just because I assumed their intelligence must guide them towards appreciating knowledge and authenticity over much more ephemeral and possibly worthless things such as prizes, fame, etc.).
I was wrong, so wrong. It's painful to remember how I felt when I realized it...
But I think the premises weren't entirely off, I just imagined people much wiser and more intelligent than they are, myself included. Anyway, I fully understand why others are shocked too.