Module development and code questions

I have made a modification to my permissions scheme (using node.module and nodeapis from OG and TAC modules) so that organic group and taxonomy access permissions work together. Node content is protected correctly now, but users can still list content they do not have access to. I'm told that I need to modify db_rewirte_sql(). Here is the blub from the node.module node_access function preamble:

I need the ability for users to apply their user points towards a purchase combined with credit card. On the summary checkout page any available user points would automatically be deducted from the pre-shipping total. The payment selection page (which forces you to select one or the other, but not both) would need to be disabled. The summary also needs to include a line indicating the user points discount.

Has anyone already made this modification and/or have any advice on how to go about it?

Thanks in advance.

Hi,
Prolly wrong place for this.
I'm just wanting to do a quick form 'thing', without writing a module since it would be overkill (also diff variations).

I've just written a quick form, and some php handling, but I don't seem to be able to get the $_POST variables, not sure if drupal is too blame. If so how do I get hold of the little tow-rags?

Hello,
I am currently working on a Drupal site... www.blackmarketartgallery.com and I'm having a little trouble with the Ecommerce module. The issue is that when you navigate to www.blackmarketartgallery.com/product it displays 3 columns, I would like to change this to two. Is there any way to do this? It's not an issue on my resolution but I have noticed when viewing the page under 1440 x 900 it is too wide and things overlap.

Hello to wholes, install the module pamper mail stops to use it with the module subscription stops than arrive mails with contents HTML, but I do not have a meal to configure it, arrive to me the notifications with the code HTML and he looks really bad neither somebody is understood can he help oneself?

Hello
I have wrote a small module to automating and manage past events
the admin can choose to delete / unsticky / unpromote / unpublish an event that past (cron hook)

is there another (a better way) doing this ?

anyway (even for academic reasons) I'll be happy to understand what is the correct way to do the query of the past events, this is my code :