Module development and code questions

Here is my javascript code, very simple:

function cart_add(nid) {
  uri = get_base_url() + '?q=cart/cartadd/' + nid;
  HTTPGet(uri, cart_update_block, nid);
}

function cart_update_block(ajaxString, ajaxResult) {
  var block = $('cables_cart');
  block.innerHTML = ajaxString;
}

It gets called from this:

I've been trying to modify the latest & greatest module to work with forum posts, rather than aggregator items... but i haven't been successful. Has anyone else modified this module in a similar manner?

It seems like it ought to be pretty easy to modify (not a lot of database queries) if i was a programmer.

here the code that needs to be modified

i would like to know if theres a drupal module for a download center or page, currently i cant find one, even in the CVS, the one in there dosent seem finished. if not intergrating paFileDB would be a great start, i'd do it but coding modules is way over my head, i can do html/php/mysql not this module code though.

Creating the module in which user edits term structure.
In the module terms are named different, presented different - the module stands completely apart of taxonomy module. There was no problem because term db tables structure are quite simple.

Now I came to the point where user should create content while he is inside one of terms.
In other words user travels through taxonomy tree editing terms and creating nodes insite terms rather then going to "create content" page and choosing terms from list.

The following text will be divided into two sections; the first one stats, and the second one is the problem.
Stats:
I am using Drupal 4.6.5.
I have PHP5.
I am trying to use the userpoints module
Problem:
I want to convert userpoints (once there are enough) to money that can be used in my Drupal store (with the ecommerce module) to buy certain things. How can I do that without actually giving the person money?

Drupal version used: 4.65.
Web server: apache2.

I'm using the single sign-on module with a master site built by me, and having a problem to log in through the same slave more then once. The problem does'nt appear while deleting the slave's site cookie and using a different session id each time.
I know that the problem is that the same slave cannot get into the first if statement of the nested if:
" if (empty($_SESSION['singlesignon_prior_sid']) || $_SESSION['singlesignon_prior_sid'] != session_id()) { ".