Phew....thanks all for your input.  My Mindstorm NXT 2.1 is now working on iMac desktop and MacPro laptop, both running on a OS X 10.6.8.  
Here's what I did:1.  Downloaded the update for NXT 2.1http://www.legoeducation.us/eng/Support/NXTSoftwareUpdates.cfm?paID=5645
2.  Downloaded the "Fantom Driver"http://us.mindstorms.lego.com/en-us/support/files/default.aspx#Driver
3.  Restarted the computer, and opened up the application/NXT 2.1.  It works!  Yeah!  Well, that's all I did though :)  Tomorrow I'll have more time programming the robot with my son.  I'll let you know if I run into any more glitches or a need to download other files (as suggested with a few other posts on several forums and listserves).
Thanks all for your help. Leandra


Date: Thu, 9 Aug 2012 13:19:07 -0400
From: [log in to unmask]
Subject: Re: [VADCFLL-L] Problem with Opening Mindstorm NXT program on MAC
To: [log in to unmask]


I had the same problem, when I updated to Mac OSX lion. I called LEGO and they were very helpful. I currently am running Mountain Lion and no problem. I have Lego NXT 2.1f5.I can try to email you the zip file if you need it.
Alex
From:  <Swayne>, Nick Swayne <[log in to unmask]>
Reply-To:  Nick Swayne <[log in to unmask]>
Date:  Thursday, August 9, 2012 12:30 PM
To:  "[log in to unmask]" <[log in to unmask]>
Subject:  Re: [VADCFLL-L] Problem with Opening Mindstorm NXT program

I haven’t coached a team for a couple years so have not updated my software since v2.0 came out.  I tried to run v2.0 on my MacBook Pro (3 years old running
 Lion) this summer and it kept crashing.  I just ordered the v2.1 software but haven’t received/installed it yet.  As soon as I get it I’ll test it out. 
 LEGO Education has been VERY supportive in the past so I recommend giving them a call.  If you discover a global issue/solution, please post it to the list. Nick From: First Lego League in Virginia and DC [mailto:[log in to unmask]]
On Behalf Of Alex
Sent: Thursday, August 09, 2012 12:21 PM
To: [log in to unmask]
Subject: Re: [VADCFLL-L] Problem with Opening Mindstorm NXT program  Have you gone to Lego Education and downloaded the update?http://www.legoeducation.us/eng/Support/NXTSoftwareUpdates.cfm?paID=5645On Thu, 9 Aug 2012 11:48:44 -0400, Leandra Velasco wrote:Hello All!  I need advice... I have a Mac desk top and Mac Pro laptop, both operating on Mac OS X 10.6.8 After loading the NXT Software v2.1 on both computers, the program is NOT opening up.  It reads:  Error code 1003/A required file is broken Has anyone had a similar issue?  Is it because the software is not compatible with Mac OS X 10.6.8?  Any suggestions in fixing this issue?Thanks a bunch!Leandra -- To UNSUBSCRIBE or CHANGE your settings, please visit https://listserv.jmu.edu/archives/vadcfll-l.html and select "Join or leave the list". -- VADCFLL administrative announcements are sent via VADCFLL-ANNOUNCEMENTS-L. Visit https://listserv.jmu.edu/archives/vadcfll-ANNOUNCEMENTS-l.html to subscribe. To UNSUBSCRIBE or CHANGE your settings, please visit 
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