Module development and code questions

I want all user uploads being run through anti-virus software. My hosting company offers the software. All I have to do, is to run the uploads in /tmp through it right after they have been uploaded via a shell_exec in PHP and to delete the uploaded file rather than move it to the uploads directory if the upload string contains "Infected". However, I don't want to put this into upload.module since I'd have to change upload.module after every update of the module or of Drupal. I want to put it in a module on its own.

Are service links incompatible with any other modules? It was working fine on my site, but it may have stopped working after a few modules were installed.

I installed the collapsiblock and it workes great!! I could set the Block collapse behavior: Collapsible, expanded by default.
But as soon as I changed the Page specific visibility settings for the BLOCK (PHP Mode):Show if the following PHP code returns TRUE. It works but suddenly no matter what settings I put in the Block collapse behavior it is ALWAYS :Collapsible, "collapsed" by default. I want it to be expanded by default.

Hi! For a module I'm working on, I would like to be able to have a bunch of checkboxes that wrap, rather than stack:

[ ] Option 1  [ ] Option 2  [ ] Option 3
[ ] Option 4  [ ] Option 5

I don't see how I can do this through the forms api. In a version of this module for 4.6, I was able to post-process the generated HTML from form_checkboxes() to remove the line breaks and divs. In another place, I actually generated the HTML directly. But I can't seem to do this in the new method.

Any suggestions?

Thanks,
Ricky

Hi! I'm working on a module which one one page displays both a table (of users, displaying the profile information) which has been created with tablesort_sql to allow sorting by various columns, and a form to allow the user to pick which columns to display. Everything works correctly when changing the sorting order — the edit parameters are properly preserved, so that the module knows which columns to display. However, when I change which columns are displayed, the 'sort' and 'order' parameters are lost, so the sorting resets itself to the default.

I have a contact form that is currently sending site visitors' questions via an email to 3 people. So that each of these three people are not duplicating the others' replies, is there a way to record messages sent through the contact form? I envision a page where all submitted inquiries are viewable in a table and the responding parties can see which nodes have no reply. Is there a current module that can do something like this or should I start developing my own?