Jeff Behnke

That is most likely a JavaScript error as the editor buttons are generated via JS

Please fix your contructor’s. This is a PHP version issue also.
Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; AI_Twitter_Widget has a deprecated constructor in wp-content/plugins/ai-twitter-feeds/ai-twitter-feeds.php on line 337

Most of the time all you have to do is change the method to __construct()

Had the same issue with a client.
Login into Authorize.net with admin credentials
Go to Account > Settings > API Login ID and Transaction Key
And generate a new transaction key.
Add that new key to the WP admin > Settings > Store > Payments > Authorize.net AIM/CIM/ARB
in the appropriate box.

Login to your database through whatever your host uses, usually phpMyAdmin

Then in your WordPress database go to the options table
Find siteurl row (its usually the first row) and change the URL back to the one that works.
Also find home row and change the URL back to the one that works.

Then check your site, it should work again.

You first need to find the performance issue. Guessing and throughing hardware at it wont solve the issue, unless that is the issue.

Get something like Newrelic on the server and maybe a benchmark plugin.
You need numbers, stats.

I dont have anything that big. I could mock it, but that wont help if the system is not the same, services, plugins, theme, etc..

The white page seems related to either the theme or a plugin.
Most likely what ever theme you are running.
Did you edit any of the files, theme or hopefully not WP core?
You may have left a BOM or white space or even a PHP parse error in there.
If the host does not show errors then you could endup with a white page.

So if you edited the theme make sure your edits are good and that there are no mistakes.

If its a downloaded third party theme try one of the default themes and see if that fixes it.

As for the MySQL issue, that is going to be a problem with the hosting. If the MySQL version is to old, its up to the host to keep that stuff up to date.

You will have to use multiple wp_footer and admin_footer
or in_admin_footer

The 2 admin footer hooks are in different spots, so it will depend on what you want for an outcome.

If you have a left sidebar in your theme and it is widgetized it can be done there.

Or you will have to add the code for it.

It all depends on what theme you are using and what it has to offer.
That will determine what it will take to add it.

Did you try chaining your CSS

#nav li a {color: red;}
#nav li a:hover {color: blue;}

Start with the parent and make sure the CSS is all using the same parent so it is not over written elsewhere.

If you need to add special id’s or classes to each item you will have to add a filter to the menus, do it manually in the Menu Admin, or use jQuery or other javascript to add them.

Seems I miss understood this feature.

Sorry