Graphic settings being overridden?

[sjchase]

I'm designing an app that lets the user select items from one list that can be moved to another list with add/remove buttons. That functionality works correctly, but when I try to set the size of the components or the panes they are in, the settings appear to be ignored. To group the components I have used nesting panes added to a tabbed panel. I've tried a few things so far, commented out in the code snippet. Being new to Java and Layout Managers in general, I'm hoping I missed something obvious. My questions are:
-how can I force the list boxes to be no bigger than a certain *maximum* size?
-why do none of the graphic overrides work, for the panes or for the components? (see attached screenshot)


The code that sets the graphical arrangement is as follows:

	  //add elements to respective panels
		  //Dimension myMax=new Dimension(200,200);//doesn't work
		  testPanel=new Panel();
		  agentPanel=new Panel();
		  runPanel=new Panel();
		  setupPanel=new Panel();
		  resultsPanel=new Panel();
		  configPanel=new Panel();
		  testPanel.setSize(300, 300);
		 agentPanel.setSize(30,30);//doesn't do anything!
		  
		  	GridBagLayout standardGrid=new GridBagLayout();
		  	GridBagConstraints lpanelC=new GridBagConstraints();//left panel
		  		 lpanelC.fill=GridBagConstraints.BOTH;
		  		 lpanelC.weightx=0.5;
		  		 lpanelC.weighty=1.0;
		  		 lpanelC.gridx=0;
		  		 lpanelC.gridy=0;
		  	GridBagConstraints rpanelC=new GridBagConstraints();//right panel
		  			rpanelC.fill=GridBagConstraints.BOTH;
		  			rpanelC.weightx=0.5;
		  			rpanelC.weighty=1.0;
		  			rpanelC.gridx=2;
		  			rpanelC.gridy=0;
		  	GridBagConstraints cboxC=new GridBagConstraints();//checkbox
		  			cboxC.weightx=0;
		  			cboxC.weighty=0;
		  			cboxC.gridx=1;
		  			cboxC.gridy=2;
		  	GridBagConstraints addBC=new GridBagConstraints();//add button
  					addBC.weightx=0.5;
  					addBC.weighty=1;
  					addBC.gridx=1;
  					addBC.gridy=0;
  					addBC.insets = new Insets(0,10,0,10);
		  	GridBagConstraints removeBC=new GridBagConstraints();//remove button
					removeBC.weightx=0.5;
					removeBC.weighty=1;
					removeBC.gridx=1;
					removeBC.gridy=1;		  	
					removeBC.insets = new Insets(0,10,0,10);
		  		  
		  
		  testPanel.setLayout(standardGrid);		  
		  testPanel.add(allTests,lpanelC);
		  testPanel.add(addTests,addBC);
		  testPanel.add(checkAllTests,cboxC);
		  testPanel.add(myTests,rpanelC);  
		  testPanel.add(removeTests,removeBC);
		  
		  agentPanel.setLayout(standardGrid);
		  agentPanel.add(allAgents,lpanelC);
		  agentPanel.add(addAgents,addBC);
		  agentPanel.add(checkAllAgents,cboxC);
		  agentPanel.add(myAgents,rpanelC);		  
		  agentPanel.add(removeAgents,removeBC);
		  
		  runPanel.setLayout(new FlowLayout()); 
		 runPanel.add(runButton);
				
		  //Run Tests tab
		 
		  //allAgents.setMaximumSize(myMax);//this doesn't work
		  //myAgents.setMaximumSize(myMax);
		  frame.setSize(800, 800);
		  setupPanel.setSize(800,800);
		  setupPanel.add(testPanel);
		  setupPanel.add(runPanel);
		  setupPanel.add(agentPanel);
		  
		  //Config tab
		  testFileLoc=new JTextField(testData);
		  agentFileLoc=new JTextField(agentData);
		  resultLoc=new JTextField(testLoc);;
		  appInstructions=new JTextArea(blah);
		  configPanel.add(testFileLoc);
		  configPanel.add(agentFileLoc);
		  configPanel.add(resultLoc);
		  configPanel.add(appInstructions);
		  configPanel.add(configButton);
		  
		  //Results tab
		  frame.add(setupTab);
		  setupTab.add(setupPanel,"Test Run Setup");
		  setupTab.add(configPanel,"Config");
		  setupTab.add(resultsPanel,"Results");
		  setupTab.setSize(800,800);  		  

		  frame.setVisible(true);
		  frame.setResizable(true);

Thanks in advance!