Anderton
I tried to duplicate this with a Sonitus effect by saving so many presets that I thought the column would extend beyond the screen. However, what happened was that it created a second column of presets with the overflow, so I can't help you there. Perhaps there's something in the way NI handles presets since you mentioned all NI products.
Maybe try using the up/down arrow keys so you can scroll down or up to the preset you want? I suppose it's not an optimum solution, but hopefully it will allow you to access the desired preset.
Thanks, Anderton and everyone else. So, yeah, it does seem like just this menu still believes I have a larger monitor, even though it's not even connected and has disappeared from Windows' display settings. The Native Instruments presets seem to make it worse because they insert their factory presets into Sonar's menu, like 128 or so of them, causing it to create 3 columns. But after the 3rd column it puts the user presets, and doesn't make a scroll bar or a fourth column. Here's a screenshot I took (that will one day disappear from this post if I accidentally delete it from my website). The presets with "Toms" in front denote that they were customized by me...it is how I save favorites, basically.
I did come up with a lame workaround which is to go into the plugin manager, which lists the presets without flaw, then place a numeric character in front of the name so that it sorts to the top. But this still only works if I remember what the presets were and which I want to sort first.