Crash when using with Refresh Header

[nickup]

Your Layout Kit is pretty cool to me, but i thought there was a bug.

if (self.collectionView.isDecelerating || self.collectionView.isDragging) {

} else {
    [self calculateMaxColumnsCount];
    [self calculateItemsInnerMargin];
    [self calculateItemsHeights];
    [self calculateSectionsHeights];
    [self calculateItemsAttributes];
}

this piece of code in preparelayout brings a lot of crash to my project.
It won't update the layout when dragging or decelerating. T T