Hi,

I have a project to do a community/social network for people to create/share multimedia contents (videos and photos of sports).

Elgg seem to be a strong base for me to work with, but I am a bit lost to customize it the way I need.

I have a strong c++ background, quite a smaller one on php (it's been a while).
My english is usually good, but I seem to struggle to understand the meaning of most documentation sentences! 

For the first set I am trying to at least change the login page (the first one!) so I had a look at the custom index mod to see how it's done but I am not sure I understand it well.

 The start.php ask elgg to change the index to index.php (from the mod file).

index.php does:

- create all the variable needed to display on the page.
- Merge it with the view/default/page/layout/custom_index.php (function elgg_view_layout)
- Display it with the elgg_view_page 

the layout does:
- check if the module is activated and display it with the variables taken from index.php

Questions?

is $params from index.php the same as $vars in custom_index.php?
I don't understand $mod_params = array('class' => 'elgg-module-highlight'); in custom_index.php
The wiki/view(http://docs.elgg.org/wiki/Views) page does not talk about the function elgg_view_layout, what is the difference between template and layout? 

what are those lines for?

// a view for plugins to extend
echo elgg_view("index/lefthandside");

 And also, is there a way to have that page to have a custom header and footer?

PS: any link to good easy to understand tutorial for creating theme/plug in would be nice too, the search function doesn't give me great resultfor 1.8!
I can't find what are the files hierarchy to have, the most important function/files to use and what they are for etc....
I had a look at easy theme also, but it have a completly different hierarchy of file!
PS2: http://community.elgg.org/groups/58806/the-idiots-guide-to-changing-elgg/ this is like the name of what I am looking for but it is not available anymore!

I will keep having a look and trying to figure things out.

Thanks.