Zorua is either a cute and interesting character, or almost completely insufferable, depending on who you ask.
Some hate Kodai for doing things that many consider far too bleak and horrible for the series, while others love him for that exact reason.
Complete Monster: The Big Bad, Grings Kodai, is a powerful businessman who discovered one of Celebi's Time Ripples. Gaining its power at the price of annihilating the nearby city's plant life, Kodai used this power for his own greed. In the current, Kodai kidnapped a Zoroark's baby Zorua, importing the baby into another region and using blackmail to force Zoroark to terrorize innocents to make himself look good. He intended to renew his abilities by touching the Time Ripple again, at the threat of once again devastating the ecosystem solely for the money. Once Zoroark tracks Kodai down, Kodai threatens Zorua's life, electrocuting it with his gauntlet to almost fatal extents to prove he was serious. Upon being tricked by Zoroark, Kodai loses it and instead electrocutes Zoroark to death in his fury, just as the two were finally being reunited. An ambitious and selfish opportunist of the worst kind, who only cared about himself, Grings Kodai managed to be one of the most despicable humans in the Pokémon franchise.
Macekre: The English dub shown on Cartoon Network was a Cut-and-Paste Translation done without The Pokémon Company's knowlege. Among other things, the editing in the dub cut out plot-relevant bits, resulting in two noticeable plot holes. The Pokémon Company's dub is generally considered better, and keeps the plot and spirit of the original version.
Moral Event Horizon: Grings Kodai forces Zoroark to allow him to obtain the Time Ripple by electrocuting her child right in front of her. Then Kodai has his Pokémon try to kill Zoroark, since he's got Zorua in the palm of his hand, and Zoroark is defenseless so long as he does. And he manages to one up himself by trying to murder Zorua and Zoroark in cold blood when they trick him, despite the fact that he could've ignored them to absorb the Time Ripple or flee. And he actually succeeded in killing Zoroark - though Celebi saved her, it doesn't change the fact that Kodai committed, thus far, the only successful cold-blooded murder of a Pokémon (all other times were accidental or just a side effect of what the villain was doing).
Narm Charm: Considering that this is Pokémon, it can actually be quite endearing for some.
Nightmare Fuel: Zoroark, once again. However, she might have been intended to be scary at a low level.
Kodai, too; he shocks people, traps them in boxes, and throws them at hard objects, and he doesn't care who he does it to.
Kodai's electrocutions; unlike the normal Harmless Electrocution, you see the victim(s) convulsing in pain and screaming in agony. While both are scary, Zorua's is far worse, as the poor thing is just a baby suffering like that, making it rather... hard to watch.
The Scrappy: Kodai is a disliked character among fans, but not in the way the movie intended. He lacks a personality and anything "cool" about him that'd make people admire him, has almost no depth beyond "ruthless executive", and him strangling Celebi and electrocuting Pokémon with no restraint at all are often considered to be far too mean-spirited for the Pokémon franchise.
Surprisingly Improved Sequel: A good number of people consider it to be the best of the Diamond and Pearl films, since it's allowed to stand on its own without having to awkwardly tie into one or two prior films.
When Zoroark is confronting the Legendary Beasts and senses Zorua getting hurt. While not played up, the simple fact is she's a mother who knows her beloved son is on the other side of town, being hurt, and thanks to the trio, there's nothing she can do about it. It shows in the fight, as she's trying her hardest to get enough distance to make it to Zorua but just can't.
The brief look on her face when she and Zorua are stumbling towards one another. Up until that moment, Zoroark has never shown anything but pure, ferocious resolve — but for an instant, she looks close to tears.