VisBio used to link all thumbnails into the displays simultaneously. This strategy had the advantage of improving animation performance. Unfortunately, other functions such as color adjustments became slower and slower as the amount of thumbnail data increased. Even worse, VisBio's memory requirements became unreasonable with sufficient thumbnail data linked to the displays.
As of v2.20, VisBio links thumbnails into the displays only as needed. You will notice substantial speed improvements among several features, as well as vast memory usage improvements, especially with larger datasets (datasets that once required more than 1 GB of RAM now need less than 100 MB). However, because this on-the-fly thumbnail linkage is more CPU intensive, animation at high frame rates requires a fast processor to keep up.
For the next major release of VisBio, we plan to investigate techniques for improving animation performance, such as the use of by-reference texturing in Java3D.