Nadya,

I consider multipick listboxes a "far to fragile" UI to ever deploy one. One mis-click by the user and all there prior selections are blown away. That's an extremely frustrating thing for a user. I think a moverlist (two list boxes, the left showing available items that get moved into the listbox on the right showing the selected items like in the view designer or event logger dialog) is a far better UI for this kind of thing.

The other UI I've used is grid based with a checkbox that allows users to select multiple items, but this doesn't have click+shiftclick to select a range functionality.

> I described this bug in other threads (see 'Flakiness behavior of listbox'). The problem is if multi-select listbox contains more than 100 items, when a user tries to scroll listbox, using mouse and scrollbar (clicking on bottom button with dnarrow), the listbox becomes a mess (I mean, one item covers another, etc.) You may try to reproduce this behavior. My colleague, who started this application, designed great class with several nice features: it has exclude checkbox and clear button. Clear button clears all selections and if I check exclude, all selections became red. This functionality remains in disable mode also, but in this case selections are in light blue/light red (rose). This control also has save/restore feature, e.g. it remembers the previous selections and restores them, when I start my form. It has some other cool features. However, this control doesn't work, as I said, if number of items are greater than 100. This bug really strikes me. Especially because application
>is completed and works. And I understand, that designing a similar behavior in grid would be a real PITA, if it's doable at all.
>
> I also noticed, that if I click on button of the form, forcing moving focus, listbox refreshes and becomes 'normal' again. So, I thought about workaround switching focus programatically in MouseUp event. It apparently helps, but not at all. So, it seems to me, that I have no choice :(