CollectionView with "half" the data only in iOS8

Question

I have this strange issue where my collection view is loading data from a plist file and its perfectly fine on iOS7, but not in iOS8.

My cells are only containing a UILabel that shows a specific item from a plist file. It's really just a list of strings. It works if I use it, the cells react properly and all is good, expect one thing : The labels don't show up. If I tap it I have the data and the program runs fine. If I browse down and up again, they reload with the proper labels.

It's really just the very first loading that does not show the labels.

I've tried putting a reloadData button to be sure it's called as late as possible, but to no avail.

Any clue?

Here is some code :

Collection view methods

- (void)collectionView:(UICollectionView *)collectionView didDeselectItemAtIndexPath:(NSIndexPath *)indexPath{
    UICollectionViewCell *cell = [collectionView cellForItemAtIndexPath:indexPath];
    cell.layer.borderColor = ClearColor.CGColor;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
    static NSString *cellIdentifier = @"TagCell";
    UICollectionViewCell *cell = [_cvTags dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];

    if (cell == nil) {
        cell = [[UICollectionViewCell alloc]init];
        [cell setRestorationIdentifier:cellIdentifier];
    }

    UILabel *lbT = (UILabel*)[cell viewWithTag:1];
    if (score == 1){
        lbT.text = [[tags objectForKey:PLIST_Plus]valueForKey:[NSString stringWithFormat:@"%i",indexPath.row]];
    }
    if (score == -1){
        lbT.text = [[tags objectForKey:PLIST_Minus]valueForKey:[NSString stringWithFormat:@"%i",indexPath.row]];
    }
    cell.contentView.backgroundColor = ClearColor;
    cell.layer.borderColor = ClearColor.CGColor;
    cell.layer.borderWidth = 3;
    cell.layer.cornerRadius = 20;
    return cell;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
    if (score == 1){
        return [[tags objectForKey:PLIST_Plus] count];
    }
    if (score == -1){
        return [[tags objectForKey:PLIST_Minus] count];
    }
    else{
        return 0;
    }
}

viewDidLoad

tags = [NSDictionary dictionaryWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"tags" ofType:@"plist"]];

plist File

It's just an XML file with a dictionary.

Note :

It's really just fine on iOS7. I have the exact same issue with a tableview on another view. But its worst. I'm filling the cells with hardcoded labels INSIDE the cellForRow method, and they still don't show until I reuse them.