Errors when "building all thumbnails/resizes" function

Hi, I have Gallery 2.X on my Windows 2003 server, running XAMPP (Apache 2.2, PHP 5.2). Whenever I run the "build all thumbnails/resizes" function in the 'Maintenance' section, I get the following output error:

Debug output for failed items:
file_exists(F:\xampp\g2data\cache\entity/1/1/112.inc)
file_exists(F:\xampp\g2data\cache\derivative/1/1/112.dat)
file_exists(F:\xampp\g2data\cache\entity/1/1/110.inc)
getParameter lock.system for core plugin
--------------------------------------------------------------------------------
(mysqli): SET NAMES "utf8"
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): update g2_SequenceLock set id=LAST_INSERT_ID(id+1);
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): INSERT INTO g2_Lock (g_lockId, g_request, g_freshUntil)
VALUES(113, 1, 1258154841)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT g_lockId FROM g2_Lock WHERE g_request=1 ORDER BY g_lockId
ASC LIMIT 1
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT COUNT(*) FROM g2_Lock WHERE g_readEntityId IN (112) OR
g_writeEntityId IN (112)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): DELETE FROM g2_Lock WHERE g_lockId IN (113)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): DELETE FROM g2_Lock WHERE g_freshUntil < 1258154812
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): update g2_SequenceLock set id=LAST_INSERT_ID(id+1);
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): INSERT INTO g2_Lock (g_lockId, g_request, g_freshUntil)
VALUES(114, 1, 1258154842)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT g_lockId FROM g2_Lock WHERE g_request=1 ORDER BY g_lockId
ASC LIMIT 1
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT COUNT(*) FROM g2_Lock WHERE g_readEntityId IN (112) OR
g_writeEntityId IN (112)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): DELETE FROM g2_Lock WHERE g_lockId IN (114)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): DELETE FROM g2_Lock WHERE g_freshUntil < 1258154813
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): update g2_SequenceLock set id=LAST_INSERT_ID(id+1);
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): INSERT INTO g2_Lock (g_lockId, g_request, g_freshUntil)
VALUES(115, 1, 1258154843)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT g_lockId FROM g2_Lock WHERE g_request=1 ORDER BY g_lockId
ASC LIMIT 1
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): SELECT COUNT(*) FROM g2_Lock WHERE g_readEntityId IN (112) OR
g_writeEntityId IN (112)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
(mysqli): DELETE FROM g2_Lock WHERE g_lockId IN (115)
--------------------------------------------------------------------------------

Error: building 112: Error (ERROR_LOCK_TIMEOUT)in modules\core\classes\GalleryStorage\GalleryStorageExtras.class at line 716 (GalleryCoreApi::error) in modules\core\classes\GalleryStorage.class at line 396 (GalleryStorageExtras::acquireWriteLock) in modules\core\classes\DatabaseLockSystem.class at line 42 (GalleryStorage::acquireWriteLock) in modules\core\classes\GalleryLockSystem.class at line 147 (DatabaseLockSystem::_acquireLock) in modules\core\classes\helpers\GalleryLockHelper_simple.class at line 176 (GalleryLockSystem::acquireWriteLock) in modules\core\classes\GalleryCoreApi.class at line 2291 (GalleryLockHelper_simple::acquireWriteLock) in modules\core\classes\helpers\GalleryDerivativeHelper_advanced.class at line 833 (GalleryCoreApi::acquireWriteLock) in modules\core\classes\GalleryCoreApi.class at line 997 (GalleryDerivativeHelper_advanced::rebuildCache) in modules\core\classes\helpers\GalleryDerivativeHelper_simple.class at line 50 (GalleryCoreApi::rebuildDerivativeCache) in modules\core\classes\GalleryCoreApi.class at line 984 (GalleryDerivativeHelper_simple::rebuildCacheIfNotCurrent) in modules\core\classes\BuildDerivativesTask.class at line 113 (GalleryCoreApi::rebuildDerivativeCacheIfNotCurrent) in modules\core\AdminMaintenance.inc at line 128 (BuildDerivativesTask::run) in ??? at line 0 (AdminMaintenanceController::runTask) in modules\core\classes\GalleryTemplateAdapter.class at line 1092in F:\xampp\g2data\smarty\templates_c\%%687683871\matrix\%%3A^3A8^3A818B59%%theme.tpl.php at line 74 (GalleryTemplateAdapter::trailer) in lib\smarty\Smarty.class.php at line 1255in modules\core\classes\GallerySmarty.class at line 61 (Smarty::fetch) in modules\core\classes\GalleryTemplate.class at line 241 (GallerySmarty::fetch) in main.php at line 506 (GalleryTemplate::display) in main.php at line 104in main.php at line 88

On another related note, Gallery seems to freeze or not respond when I upload large photos individually. After this, the large photos are not appearing on the webstite, rather only "containers" which indicate broken links to images are shown.

Please help.
Thanks in advance!