Upgrade from Revo Version 2.2.6 to 2.3.6 Now pages don't load

Hi Guys,
Following some previous advise here I have decided to bite the bullet and upgrade my system.
I have a test server running the same MODX version of my production server so I decided to upgrade that first.

The upgrade seemed to go well. The pre-install tests all passed.

The Manager screen loads and looks nice but I get a plain white screen when I dig down to my sites content.
i.e. This URL just shows a plain white screen. http://test.com.au/manager/?a=resource/update&id=4

When I try and load the published pages in my browser a rubbish looking page comes up with all of the graphics missing and the format all over the place.


The error.log shows lots of messages a lot like this
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/dashboard
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/topmenu
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/file
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/action
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/login
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/action
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/login
[2015-08-19 16:20:24] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/login
[2015-08-19 16:20:25] (ERROR @ /manager/index.php) Error caching lexicon topic lexicon/en/core/dashboard
<SNIP>


I also saw this error message when updating

Error updating table for class modResource
Array
(
[0] => 42000
[1] => 1061
[2] => Duplicate key name 'cache_refresh_idx'
)

And I also copied this text from a pop up screen at he end of the install or when I first opend the manager but can't remember exactly where.

/*
* MODX Console Output
*
* @date 2015-08-19 15:17:47
*/
Could not cache system settings.
Could not cache context settings for mgr.
Could not cache context settings for web.
PHP warning: unlink(/var/www/core/cache/lexicon_topics/lexicon/en/cronmanager/default.cache.php): Permission denied
PHP warning: closedir(): 135 is not a valid Directory resource
PHP warning: unlink(/var/www/core/cache/lexicon_topics/lexicon/en/core/default.cache.php): Permission denied
PHP warning: closedir(): 138 is not a valid Directory resource
PHP warning: unlink(/var/www/core/cache/scripts/elements/modsnippet/38.cache.php): Permission denied
PHP warning: closedir(): 143 is not a valid Directory resource
PHP warning: unlink(/var/www/core/cache/includes/elements/modsnippet/38.include.cache.php): Permission denied
PHP warning: closedir(): 148 is not a valid Directory resource
PHP warning: unlink(/var/www/core/cache/action_map/mgr/actions.cache.php): Permission denied
PHP warning: closedir(): 159 is not a valid Directory resource
Error caching script elements/modplugin/4
Processing automatic publishing dates
-> 0 documents were published.
-> 0 documents were unpublished.
Regenerating system settings cache: Refresh successful!
Regenerating the context caches
-> mgr: Refresh successful!
-> web: Refresh successful!
/* EOF */

I ran the setup again but didn't receive any of the above errors the second time.
However the web pages have exactly the same problems.

Obviously there could be some permissions problems on my file system.
I don't really know what I should be setting the permissions to?

Any ideas what I'm doing wrong?
(Yes the site was working fine on 2.2.6)


Thanks in Advance
David.

Stop Looking I may have found it

I noticed the core/cache folder was owned by root and the group is www-data
Some of the folders within cache were also owned by root.

I changed everything to owner www-data and now it seems to be working OK.

Obviously more testing to do.

I wish there was a definitive list somewhere of recommended file and folder permissions.
I have no idea if my site is secure or flapping in the breeze.

I don't have a cmd line access to the production server so it isn't so easy for me to fix permission problems.
However if the guys that originally set it up did a good job I shouldn't encounter the same problem in production.
My test server setup was a bit of a cludge getting it to mirror production was a bit of a task for me

Regards
David

Ownership and permissions depend entirely on the server configuration, so there's no way to say what ownership and permissions there should be.