Hang on launch DEVONThink Pro Office 1.5.4

Newly installed DEVONThink Pro Office 1.5.4, upgrading a previous 1.5.3 installation. Opening the database (stored on an AFP server) now spins for nearly an hour; 1.5.3 opened it in seconds.

                                            3195 start
                                              3195 start
                                                3195 start
                                                  3195 -[_BRN_ initWithContentsOfDirectory:override:readOnly:fileName:fileExtension:count:backup:numberOfBackups:inFolder:mapping:swapIn:neuralNetClass:containerClass:containerSize:atomicClass:atomicSize:owner:progress:error:]
                                                    3195 -[_NNT_(PrivateIO) initNeuronsBytes:length:]
                                                      2089 -[_NNT_(PrivateIO) initNeuronsBytes:length:]
                                                      1105 +[_ASt_ newWithPersistentBytes:length:buffered::inMemory:position:inFile:zone:]
                                                        1098 __memcpy
                                                          1098 __memcpy
                                                        4 +[_ASt_ newWithPersistentBytes:length:buffered::inMemory:position:inFile:zone:]
                                                        3 NSAllocateObject
                                                          3 _internal_class_createInstanceFromZone
                                                            2 malloc_zone_calloc
                                                              1 __spin_lock
                                                                1 __spin_lock
                                                              1 szone_calloc
                                                                1 __bzero
                                                                  1 __bzero
                                                            1 _internal_class_createInstanceFromZone
                                                      1 -[_TNRN_ initNeuronInNeuralNet:atomic:setID:dendriformCapacities:::]
                                                        1 -[_NRN_ initNeuronInNeuralNet:atomic:setID:dendriformCapacities:::]
                                                          1 CFRetain
                                                            1 -[NSObject retain]
                                                              1 __CFDoExternRefOperation
                                                                1 CFBagAddValue
                                                                  1 __CFBagFindBuckets2
                                                                    1 __CFBagFindBuckets2

Downgrading to 1.5.3 seems to fix it. Mac OS X 10.5.5, 2Gb Macbook Pro.

Does Tools > Verify & Repair report any problems? Or has been anything logged to the system console (see /Applications/Utilities/Console.app)?