Upgraded LR1 - LR3 Catalog: blank Grid, non functioning app

Question

I've been dealing with support on this, but they're utterly useless, taking days to get back to me and spinning me over troubleshooting 101 stuff.
Problem:
Upgraded a perfectly working LR1 catalog to LR3.  No issues during upgrade.
Upon trying to use the LR3, the first thousand or so of my photos show up in Grid, but everything after that is blank. By that I mean, a grid cell is drawn, but LR3 doesn't display a thumbnail, or any cell extras or metadata.
Clicking on one of these empty cells gives me a thumbnail frame and some metadata (slowwwwly).
Going to Loupe View on a non-empty cell gives me a "Loading..." spinner and an unrendered thumbnail preview (CPU is not ramping up at all)
Going to Loupe View on an empty cell just gives me a blank screen (CPU is not ramping up at all)
Develop module does load the picture, but slowly.
When I quit, the app freezes up completely, with beachball.  Must force-quit (after giving it 20 minutes in case it was actually trying to do something)
Initially, when I load LR3, my CPU runs high, 75%, like it's working on something.  Then it just cuts out as if it's given up.
Console output when this happens is the following:
6/17/10 7:27:38 PM Adobe Lightroom 3[518] ServerProcess [AsyncDataServer( Lightroom 3 Catalog.lrcat )] ERRORSERVER<AsyncDataServer( Lightroom 3 Catalog.lrcat )>: A command threw an exception.
6/17/10 7:27:38 PM Adobe Lightroom 3[518] ServerProcess [AsyncDataServer( Lightroom 3 Catalog.lrcat )] ERROR Error: ?:0: attempt to perform arithmetic on field '?' (a nil value)
6/17/10 7:27:38 PM Adobe Lightroom 3[518] Error initializing alternate universe. bad argument #1 to 'pairs' (table expected, got nil)
System:
MacBook Pro Core2Duo 2.1Ghz 3GB RAM, 500GB Drive.
Initially Mac OS 10.5.8, but I tried upgrading to 10.6.3 and 10.6.4 (no luck).
Library: 21,000 photos
Other things I've tried:
Trashing all LR3 prefs, caches (running YASU), LR preview caches, plists, extensions, reinstalling, restarting -- no luck
Noticed it was copying the LR1 prefs plist, so I archived that.  LR3 generated a new pref, but no help
Downloaded LR2 Demo, upgraded LR1 Catalog to LR2 Catalog (which works perfectly, no issues), and then LR2 Cat -> LR3 -- no luck
Checking integrity of Catalog in LR1 and LR2 (no problems) and LR3 when upgrading (no problems)
LR3 runs fine on an empty catalog and if I point it at my photo folder and import everything, it's ok (with none of my 3 years of modifications of course).
Is my only option to write out LR1 data to sidecar files and then setup a new Catalog in LR3?

Answer 1

Well, on top of having full access to the photo files, LR obviously has proper permissions to affect the files it generates in the AppSupport>Adobe>Lightroom folder, the Caches>Lightroom folder, the Pictures>Lightroom folder and the Preferences> folder, otherwise it wouldn't be able to build a new catalog, new prefs, new caches and so forth when I generate a new empty catalog.
I really doubt this is a permissions voodoo issue or a monitor profile issue.
LR3 works fine with a brand new catalog (and all the same Photo files).
LR1 and LR2 have absolutely no problem with my catalog and photo files. 
LR2 upgrades my LR1 Catalog without issue.
LR3 fails with my upgraded catalog (and all the same photo files)
Unless I'm missing something in my logic tree here, it seems to me this is obviously a problem with LR3 upgrading my Catalog. 
Other people's catalogs upgrade fine, and that's dandy, but my catalog doesn't upgrade AND it fails with exactly the same error message every time in the Console (See original post), which seem to be related to some internal db issue, dividing by zero, nil values. 
Something ain't being handled right by LR3 that previous versions of LR had no problem with.