Support image fields with multiple images

I use timeline to show the creation date of my nodes, and basically the module works like a charm. Some of my nodes have an CCK image field, and this is used in the advanced visualization settings of the timeline style. If the node has an image it is shown as little preview in the timeline.
This only works properly if the CCK image field is restricted to one single image (in the field settings). If the CCK image field allows multiple images (which I need because use of the images is not exclusively for the timeline) the display of the images in the timeline is not correct - entries with image have none, some entries without an image have an image, but I can't really make out a pattern. If I put the CCK image field settings back to only one image the timeline view works fine.
I also show the same images in the pop-up boxes of the timeline, and that works fine even if the CCK field is set to multiple images - with the grouping option in the image I can restrict to only show one (the first) image in the pop-up.
It seems that the icon selector in the advanced visualization settings refers to an image field in the view, but it does seem not use the selection criteria specified for this field?