[Owncloud] Owncloud 6 update error

[Nicolas Mora]

Hello,

I'm trying to update Owncloud to the last 6 stable release but I'm 
having problems during the process.

I uncompress the owncloud 6 package over the existing owncloud 5.0.13 
folder and here are the current problems I encoutered :

1- lib/config.php issue
right after decompressing and changing owner of the ownloud folder, the 
owncloud page is blank. The apache error log says
"Cannot redeclare class OC_Config in /usr/local/owncloud/lib/config.php 
on line 41"
I saw on an owncloud issue (I don't remember where unfortunately) that I 
should delete the file owncloud/lib/config.php, which I did, and it 
worked, until the next problem.

2- Duplicate entry 'user_pwauth-installed_version' for key 'PRIMARY'
The automatic update program launches but stops right away with the 
following error message :
An exception occurred while executing 'ALTER TABLE `oc_appconfig` ADD 
PRIMARY KEY (`appid`, `configkey`)': SQLSTATE[23000]: Integrity 
constraint violation: 1062 Duplicate entry 
'user_pwauth-installed_version' for key 'PRIMARY'
If I run the following query, the installation can continue :
delete from oc_appconfig where appid='user_pwauth' and 
configkey='installed_version';

And then everything looks to be fine, except that automatic login 
doesn't work, and after entering my credentials, I have the following 
error message :
  An exception occurred while executing 'SELECT `fileid`, `storage`, 
`path`, `parent`, `name`, `mimetype`, `mimepart`, `size`, `mtime`, 
`storage_mtime`, `encrypted`, `unencrypted_size`, `etag` FROM 
`oc_filecache` WHERE `storage` = ? AND `path_hash` = ?': 
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'storage_mtime' 
in 'field list'

And then I stopped there...

I can restore my 5.0.13 backup and restart from there, should I try 
something else ?

/Nicolas