Crash while nudging: Crash report included: Undo Stack?

I've been using CS for just a few weeks, and I find one crash or data loss has happened repeatedly. I had previously been using AI 10, and never saw anything like this.

Generally this happens as I nudge elements on a page. I have noticed on certain occasions that after several nudges (generally of text blocks) the elements I have been nudging simply disappear from the document. Undo will not bring them back. I have to revert or otherwise reopen the disk copy to retrieve the lost elements.

Has anyone else seen this?

Previously this did not crash the application, but this time it did. Here's the crash report:

Date/Time: 2004-08-28 17:11:53 -0500
OS Version: 10.2.8 (Build 6R73)
Host: Jean-Proberts-Computer.local.

Command: Illustrator CS
PID: 833

Exception: EXC_BAD_ACCESS (0x0001)
Codes: KERN_INVALID_ADDRESS (0x0001) at 0x14e382e0

Thread 0 Crashed:
#0 0x0033b2b0 in ObjectDispose__FP9ArtObject
#1 0x004fd138 in _dt__29undo_art_object_new_dispose_tFv
#2 0x00659d04 in _dt__21CAIJournalTransactionFv
#3 0x00a753d4 in ErasePast__11iCAIJournalFRC48Ref<16CAIJournalMarke r,Q213Counte #4 0x00a4d57c in Commit__19PluginUndoOperationFP11Transaction #5 0x00664678 in Release__11TransactionFP15CAIDocumentView #6 0x006648fc in CommitPast__9UndoStackFv #7 0x00864af8 in Clear__9UndoStackFv #8 0x00a6d490 in UndoReleaseView__FP15CAIDocumentView #9 0x00a60ea0 in ArtCloseGeneral__FP17CAIDocumentWindowP11CAIADMEve ntUcUc #10 0x00a60718 in CommandCloseEx__FP17CAIDocumentWindowP11CAIADMEven tUcUcUc #11 0x00a60580 in CommandClose__FP17CAIDocumentWindowP11CAIADMEvent #12 0x00a60458 in OnCloseHitNotifier__17CAIDocumentWindowFv #13 0x00c9bde4 in 0xc9bde4 #14 0x969a2c54 in DispatchEventToHandlers #15 0x969a2fbc in SendEventToEventTargetInternal #16 0x969a63d0 in SendEventToEventTargetWithOptions #17 0x96a78114 in SendWindowEvent #18 0x969dd4a0 in HandleWindowEvent #19 0x969ee2f8 in StandardWindowEventHandler #20 0x969a2c54 in DispatchEventToHandlers #21 0x969a2fbc in SendEventToEventTargetInternal #22 0x969b5494 in SendEventToEventTarget #23 0x96a7833c in SendEventFromMouseDown #24 0x96a51d1c in HandleWindowClick #25 0x96a78294 in HandleMouseEvent #26 0x969ee2ec in StandardWindowEventHandler #27 0x969a2c54 in DispatchEventToHandlers #28 0x969a2fbc in SendEventToEventTargetInternal #29 0x969b5494 in SendEventToEventTarget #30 0x969c07dc in _Z25HandleMouseEventForWindowP15OpaqueWindowPtrP14 OpaqueEventReft #31 0x969b9934 in _Z16HandleMouseEventP14OpaqueEventRef #32 0x969b287c in _Z29ToolboxEventDispatcherHandlerP25OpaqueEventHan dlerCallRefP14OpaqueEventRefPv #33 0x969a2d0c in DispatchEventToHandlers #34 0x969a2fbc in SendEventToEventTargetInternal #35 0x969b5494 in SendEventToEventTarget #36 0x00a7ad40 in EventLoopEventHandler #37 0x969a2c54 in DispatchEventToHandlers #38 0x969a2fbc in SendEventToEventTargetInternal #39 0x969a63d0 in SendEventToEventTargetWithOptions #40 0x969b2940 in _Z29ToolboxEventDispatcherHandlerP25OpaqueEventHan dlerCallRefP14OpaqueEventRefPv #41 0x969a2d0c in DispatchEventToHandlers #42 0x969a2fbc in SendEventToEventTargetInternal #43 0x969b5494 in SendEventToEventTarget #44 0x969b7258 in _Z22ToolboxEventDispatcherP14OpaqueEventRef #45 0x96ab4e38 in HLTBEventDispatcher #46 0x96ab4d08 in RunApplicationEventLoop #47 0x00a7a9d8 in MiEventMainLoop__Fv #48 0x001e6ca4 in RunApp__14CAIApplicationFv #49 0x001d7eec in main

Thread 1:
#0 0x90042588 in semaphore_timedwait_signal_trap
#1 0x9003e7b4 in _pthread_cond_wait
#2 0x90233198 in TSWaitOnSemaphoreCommon
#3 0x9023bf78 in TimerThread
#4 0x90020c28 in _pthread_body

PPC Thread State:
srr0: 0x0033b2b0 srr1: 0x0000f030 vrsave: 0x00000000
xer: 0x00000000 lr: 0x004fd138 ctr: 0x004fd0f0 mq: 0x00000000
r0: 0x004fd138 r1: 0xbfffe020 r2: 0x026f6000