We cannot display this gallery using offset and pagination loops

Hi. I am having probs with widget slideshow.

It worked pefectly until i did some modify to my loops for displaying posts.

i use two loops. One to show the 1st post, and offset to display others excluding the previous:

my code:

function my_post_limit($limit) {
	global $paged, $myOffset;
	if (empty($paged)) {
			$paged = 1;
	}
	$postperpage = intval(get_option('posts_per_page'));
	$pgstrt = ((intval($paged) -1) * $postperpage) + $myOffset . ', ';
	$limit = 'LIMIT '.$pgstrt.$postperpage;
	return $limit;
} //end function my_post_limit

1st loop:

<?php $cat_id = get_query_var('cat'); ?>
<?php if ($paged < 2 ){
	$post_query = 'cat='.$cat_id.'&posts_per_page=1'; ?>

				<?php query_posts( $post_query ); ?>
					<?php if (have_posts()) : ?>
						<?php while (have_posts()) : the_post();

2nd loop using offset and pagination:

<?php add_filter('post_limits', 'my_post_limit'); ?><?php
global $myOffset;
$myOffset = 1;
$temp = $wp_query;
$wp_query= null;
$wp_query = new WP_Query();
$wp_query->query('cat='.$cat_id.'&offset='.$myOffset.'&paged='.$paged);
?>

<div id="posts-list-category">
	<?php if (have_posts()) : ?>
		<?php while ($wp_query->have_posts()) : $wp_query->the_post(); ?>

WELL. after using add_filter(‘post_limits’, ‘my_post_limit’);
images on widget slidshow disappear and i get We cannot display this gallery
If i remove the filter. slideshows works but pagination is broken.

any help?

https://www.ads-software.com/plugins/nextgen-gallery/