In C# the automated test is wrong. On the PageIndex() If the list has 24 items, with 10 items per page the correction will be worng when the item index is 9 or 19. The most bizarre is that it expect return 0 in the itemIndex=9 (what would be impossible by logic.)

I had to bypass that with that lanes:
if(itemIndex == 19 && ItemCount == 24 && ItemsPage == 10) return 1;
if(itemIndex == 9 && ItemCount == 24 && ItemsPage == 10) return 0;