I may have one suggestion: the file I/O becomes a bottleneck in my application since saving the meta-data of a task (large image sequences) costs almost as much time as processing the task. Maybe it helps a lot if the file I/O can be replace by shared memory functions and there is a new Matlab library for use: http://www.mathworks.com/matlabcentral/fileexchange/28572-sharedmatrix. I think it is a perfect complement to your library.
21 Oct 2010
MIP, Color, Slice and Shaded 3D (shearwarp) Volume Rendering, interactive 3D view/measurement GUI
Author: Dirk-Jan Kroon
This is no question a wonderful tool for visualization in Matlab.
One bug I found: Matlab crashes after compiling the c mex files. My Matlab version is r2009a, os is Win XP.