Errors upgrading from Gallery 2.0 to 2.3

Gallery version (not just "2"):Upgrading from 2.0 to 2.3
PHP version (e.g. 5.1.6):don't know
PHPInfo Link (see FAQ):don't know
Webserver (e.g. Apache 1.3.33):don't know
Database (e.g. MySql 5.0.32):don't know
Activated toolkits (e.g. NetPbm, GD):
Operating system (e.g. Linux): Linux
Browser (e.g. Firefox 2.0):IE 8

My website is seeyouontheriver.com hosted by Lunarpages

I get the following error message in trying to upgrade to version 2.3 (step 4 upgrade core)

Error (ERROR_MISSING_VALUE) : Undefined map: GalleryPluginParameterMap
•in modules/core/classes/GalleryStorage.class at line 1256 (gallerycoreapi::error)
•in modules/core/classes/GalleryStorage.class at line 1248 (mysqlstorage::describemap)
•in modules/core/classes/GalleryStorage/GalleryStorageExtras.class at line 979 (mysqlstorage::describemap)
•in modules/core/classes/GalleryStorage.class at line 521 (gallerystorageextras::addmapentry)
•in modules/core/classes/GalleryCoreApi.class at line 2955 (mysqlstorage::addmapentry)
•in modules/core/classes/helpers/GalleryPluginHelper_medium.class at line 364 (gallerycoreapi::addmapentry)
•in modules/core/classes/helpers/GalleryPluginHelper_medium.class at line 309 (gallerypluginhelper_medium::_addparameter)
•in modules/core/classes/GalleryCoreApi.class at line 483 (gallerypluginhelper_medium::setparameter)
•in modules/core/classes/GalleryPlugin.class at line 526 (gallerycoreapi::setpluginparameter)
•in modules/core/CoreModuleExtras.inc at line 3323 (coremodule::setparameter)
•in modules/core/CoreModuleExtras.inc at line 530 (coremoduleextras::_createaccesslistcompacterlock)
•in modules/core/module.inc at line 486 (coremoduleextras::upgrade)
•in modules/core/classes/GalleryModule.class at line 175 (coremodule::upgrade)
•in upgrade/steps/UpgradeCoreModuleStep.class at line 85 (coremodule::installorupgrade)
•in upgrade/index.php at line 186 (upgradecoremodulestep::processrequest)