any step-by-step instructions to upgrade 2.0.3.1 to 2.1.0.2

Hello.
I would really appreciate finding some detailed instructions on how to perform the upgrade from 2.0.3.1 to 2.1.0.2 and the troubleshoots to expect. I just run the upgrade on testing environment and i got lots of errors, syntax errors, etc, added some new tables to the db, etc, some got fixed, but still getting some problems in users API. May be understanding what exactly has changed, would help. Or may be there are some pre-made fixes available to avoid most of this troubles? And how stable is this new version? Should i go for it or should i wait? Has anyone performed this upgrade here? Are you happy with it? For instance API showing invalid arguments error like this:
Notice: Error: Unknown column 'name' in 'order clause'
Error No: 1054 SELECT * FROM `oc_api` ORDER BY name ASC LIMIT 0,20 in ....../vqmod/vqcache/vq2-system_library_db_mysqli.php on line 55
Notice: Trying to get property of non-object in ........admin/model/user/api.php on line 77
Warning: Invalid argument supplied for foreach() in .....admin/controller/user/api.php on line 174
Anyone knows what to do with this?

looking forward the answer too
the official documentation seems like outdated
http://docs.opencart.com/upgrading/

Hi lovenatural,

Many post about this. This should get you on your way - http://www.randemsystems.com/support/op ... n-2-1-0-1/

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