Theme development

How do I remove what is overriding in my Drupal7 site?
The problem is that, whenever I make changes and save, only parts of them do take effect and most of it does not and when I look at it on css it shows that the changes I made have been overridden by something else.

Could anyone please help me fix it?
And yes, I'm new to Drupal.

is there a basic theme that is not based/dependant on other core themes (zen, omega, etc) with every basic template possible (as example and fully commented would be great) and a css file with only the classes names fully commented available?

I'm trying to learn drupal theming but it seems most if not all of the docs/tutorials out there is based off on another core themes or a duplication/edit of an existing themes. Tried several "Basic/barebones" theme from the drupal themes section but in the end it always resort to forcing a starterkit/subtheme from it.

Where and how to add local CSS?

I recently installed the Drupal 7 Spark distribution, started a site with it and need to make some simple CSS modifications or additions (in this case some styling of a web form using Skybound's Stylizer).

Where would I put my CSS code and how would I hook it into Drupal (Spark with the Default Theme of Spark, which I suspenct to be Responsive Bartik 7.x-1.0-beta1+2-dev (Standard-Theme), since I haven't changed it).

I've started completely over from a fresh install of D7 with only the delta/omega tools/context/ctools and the admin toolbar mod being added.

I've installed the Omega 3.x theme by 'install from a file' following all directions from: https://drupal.org/node/1298692

It all works fine until I actually enable and make my subtheme the default. Then, once I navigate from enabling the theme, all I see is white.

I have limited access to the site by using direct url but what could be going on?

So, I have an amazing new theme I have developed with a designer that is currently in PSD format.

What is the best route to go to build this into an awesome drupal theme?

Should I take advantage of the designers willingness to convert it to HTML5/CSS and then find a programmer to build it into a drupal theme from that?

Should i find a programmer who can go straight from PSD to Drupal theme?

Or, Should I find a programer to take it to HTML/CSS and then on to a Drupal theme?

Very interested in your input!

I am making a new panel layout. I have copied from a layout that works and made adjustments to the inc, tpl and css files.

In the admin system, I can select the layout on the Layout screen, but when I go to the Content screen, the panels are not showing up as expected. As a result, I cannot add content to the panels.

My inc file is as follows:

<?php
// Plugin definition
$plugin = array(
'title' => t('Top Level New'),
'category' => t('-New Layouts-'),
'icon' => 'toplevel_new.png',
'theme' => 'toplevel_new',
'css' => 'toplevel_new.css',
'panels' => array(
'row1col1-6' => t('Row 1 Column 1-6 (Slideshow)'),
'row2col1-3' => t('Row 2 Column 1-3 (Destinations)'),
'row2col4-6' => t('Row 2 Column 4-6 (New to Sailing)'),
'row3col1-2' => t('Row 3 Columns 1-2 (Holiday 1)'),
'row3col3-4' => t('Row 3 Columns 3-4 (Holiday 2)'),
'row3col5-6' => t('Row 3 Columns 5-6 (Holiday 3)'),
'row4col1' => t('Row 4 Column 1 (Feature 1)'),
'row4col2' => t('Row 4 Column 2 (Feature 2)'),
'row4col3' => t('Row 4 Column 3 (Feature 3)'),
'row4col4' => t('Row 4 Column 4 (Feature 4)'),
'row5col1' => t('Row 5 Column 1 (Brochure)'),
'row5col2' => t('Row 5 Column 2 (Newsletter)'),
'row5col3' => t('Row 5 Column 3 (Schools)'),