We have a large site, so need to use the silent upgrade.

This time last year we did a large upgrade from 5.2 to 6.1. None of our attempts worked, so we sent our code+database to Sugar and after a week they converted it and sent the data back. We simply installed it - some data was lost, but we had being trying for weeks to do it ourselves. I assume it's not a beta version - it's Version 6.1.0 (Build 5389)

Now it's time to upgrade to 6.3.
Tried the silent upgrade, but it failed.
Warning: require(modules/Connectors/connectors/sources/ext/rest/insideview/mapping.php): failed to open stream: No such file or directory in /var/www/sugarcrm610/modules/UpgradeWizard/uw_utils.php on line 5375
Fatal error: require(): Failed opening required 'modules/Connectors/connectors/sources/ext/rest/insideview/mapping.php' (include_path='/var/www/sugarcrm610/include/..:.:/usr/share/php:/usr/share/pear') in /var/www/sugarcrm610/modules/UpgradeWizard/uw_utils.php on line 5375

I checked the folder, and sure enough, 6.1.0 had no folder called insideview.

I looked at the upgrade log and there were a few errors.
The final lines were:
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - Begin upgrade_connectors
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - End upgrade_connectors
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - Looks like we need to enable the InsideView connector
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - Begin upgradeEnableInsideViewConnector
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - Used default mapping

I'm not sure if the problem is related to an earlier error in the log:
Thu, 08 Dec 2011 15:00:56 +1100 [UpgradeWizard] - Error retrieving silent upgrade var for origVersion: cache dir is cache/ -- full cache for $silent_upgrade_vars_loaded is array ( 'vars' => array ( ),)

I tried to login to the site (luckily the dev version), and it's dead.
No Sugar, just a page of various errors such as:
VardefManager::include_once(cache/modules/Users/Uservardefs.php) [vardefmanager.include-once]: failed to open stream: No such file or directory in /var/www/sugarcrm610/include/SugarObjects/VardefManager.php on line 256
Warning: VardefManager::include(cache/modules/Administration/Administrationvardefs.php) [vardefmanager.include]: failed to open stream: No such file or directory in /var/www/sugarcrm610/include/SugarObjects/VardefManager.php on line 125

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /var/www/sugarcrm610/include/SugarObjects/VardefManager.php:256) in /var/www/sugarcrm610/include/MVC/SugarApplication.php on line 481


Q1. Is this all because the cache was full?
Q2. How do I clear/empty the cache folder if I can't login?
Q3. Can I disable insideview from the upgrade if it's going to cause problems?

cheers