Add multiple blocks in library browser

Hi, I need to create a custom library with 25 simulink blocks for dual quaternion operations. Each block describes a particular algebraic operation (sum, product, norm, etc.): I have each single block saved in a folder as an .slx file. I tried using slblock.m to add all the blocks to a custom library, but only one block gets added. How can i solve the problem? Right now I'm using this code:

function blkStruct = slblocks
% Copyright 1998-2001 HUMUSOFT s.r.o. and The MathWorks, Inc.
% $Revision: 1.3 $ $Date: 2001/05/11 13:52:59 $ $Author: barnard $

% Name of the subsystem which will show up in the
% Simulink Toolboxes subsystem.
blkStruct.Name = ['My Toolbox'];

% The function that is called when
% the user double-clicks on this icon.
blkStruct.OpenFcn = 'add';
blkStruct.OpenFcn = 'multiply';

blkStruct.MaskInitialization = '';

% Define the library list for the Simulink Library browser.
% Return the name of the library model and its title
Browser(1).Library    = 'add';
Browser(1).Name       = 'My Toolbox';
Browser(2).Library    = 'multiply';
Browser(2).Name       = 'My Toolbox';

blkStruct.Browser = Browser;