Possible incompatibility with NextGEN gallery plugin

I’m using WP 3.6 and Posts 2 Posts plugin 1.6.2. I have one main CPT called ‘participant’ which is connected to 2 other CPTs called ‘event’ and ‘group’. When viewing a particular ‘participant’ post, I normally see 2 boxes in the sidebar: ‘connected events’ and ‘connected groups’.

Since I updated WP and all plugins including P2P (edit: and NextGEN gallery, which seems to be the one conflicting with P2P), I now have this error message in these 2 boxes:

WordPress database error: [Unknown column ‘ids’ in ‘field list’]

SELECT
    wp_posts.*, wp_p2p.*
FROM wp_posts
INNER JOIN wp_p2p
LEFT JOIN wp_p2pmeta AS p2pm_order
    ON ( wp_p2p.p2p_id = p2pm_order.p2p_id AND p2pm_order.meta_key = 'order' )
WHERE 1=1
    AND wp_posts.post_type = 'event'
    AND (wp_posts.post_status <> 'trash' AND wp_posts.post_status <> 'auto-draft')
    AND (wp_p2p.p2p_type = 'participant_to_event'
        AND wp_posts.ID = wp_p2p.p2p_to
        AND wp_p2p.p2p_from IN (
            SELECT ids
                FROM wp_posts
                WHERE 1=1
                    AND wp_posts.ID IN (1889)
                    AND wp_posts.post_type = 'participant'
                    AND (wp_posts.post_status = 'publish'
                        OR wp_posts.post_status = 'future'
                        OR wp_posts.post_status = 'draft'
                        OR wp_posts.post_status = 'pending'
                        OR wp_posts.post_status = 'private')
            ORDER BY wp_posts.post_date DESC )
        )
ORDER BY p2pm_order.meta_value+0 ASC, wp_posts.post_date DESC

https://www.ads-software.com/plugins/posts-to-posts/