Removing items from the admin bar menu

Hi community. This is my first post, and I am new to the word press eco system. I am on my second project using WP. The first was a simple shop/website. The second is a little more challenging.
My background is IT/Software (PL/SQl, Shell, early VB, a little Pl/M which is a precursor to C and such like). I have also supported various web based systems over the years, running on apache/IIS Jboss/Weblogic/Websphere and so on. However, I have never worked with HTML or PHP. It is time to learn.

What I am trying to achieve is the following.
On a multisite install of marketpress 2.9.5.3. I want my users to be able to upload a product, but no other admin style privileges.. So in order to do this I have tried a few things so far.

I am using: marketpress 2.9.5.3. “WP_hide_admin_bar”, “User Account Manager” and “User Role Editor” plugins.

First attempt:
I have created a new role based on the Admin and used an editor and removed most of privileges. This got quite close, to what I wanted to achieve – I had the Admin bar available to my user base, and the only item on there was the “+NEW” menu. I managed to de-select the privileges to the extent that the only “+NEW” items they could add were pages and products. This was progress and close to what I wanted.
I started to suspect that a product is simply a type of “post” and therefore restricting the users rights/privileges will always allow the user to add a page or a product. I do not want them adding pages. The reason I started to suspect this is because the new “product” resolves to –

/wp-admin/post-new.php?post_type=product

and a page resolves to:
/wp-admin/post-new.php?post_type=page.

So it looks like a product and a page are types of post. As soon as I enable an ability to edit pages I get both, and I cannot seem to set a permission for a “product only”. Presumably because a product is part of Marketpress and not part of WP.

I then tried changing the user role *back* to a subscriber thus removing the admin bar altogether and creating a URL link to the /wp-admin/post-new.php?post_type=product on a separate page (restricted to only registered users).
However, I get insufficient privileges kind of error. Ok, I thought, we are getting somewhere…what about allowing the subscriber permission to edit a post but also activate the hide admin bar plug in. Breifly I thought I had what I wanted, but no the admin bar comes back once the permission is set to edit a post in the “user role editor”.
—————————————————

Next I reassigned my user back to a role based on the admin role, thus re-enabling the admin bar for them..

I used the IE developer interface [F12] and object picker to identify the ID of the objects i want to remove.

I then edited functions.php and used this kind of approach: OK – so a bit hit and miss in desperation to try and get the menu to have nothing other than the +New>>Product.

function remove_admin_bar_links() {
global $wp_admin_bar;
$wp_admin_bar->remove_menu(‘wp-logo’);
$wp_admin_bar->remove_menu(‘wp-admin-bar-new-content-default’);
$wp_admin_bar->remove_node(‘wp-admin-bar-new-content-default’);
$wp_admin_bar->remove_menu(‘wp-admin-bar-new-post’);
$wp_admin_bar->remove_node(‘wp-admin-bar-new-post’);
}
add_action( ‘wp_before_admin_bar_render’, ‘remove_admin_bar_links’ );

I see that using “remove_menu” does remove top level items from the menu, for example the first remove line takes out the WP logo. But what I couldnt do was remove the actual menu items from the menu. I.e. I could remove the entire “+new” menu, but not remove the item “post” from the “+New” menu on the admin bar.

I tried coding a few thingss – “remove_menu” and “remove_menu_item” and “remove_node”. None of these achieved what I wanted.

I then tried a different approach and edited class-wp-admin-bar.php like below – this resulted in my user loosing a lot of the left side bar and the entire admin_bar 🙂

add_action( ‘admin_bar_menu’, ‘remove_page’, 999 );
function remove_page( $wp_admin_bar ) {
$wp_admin_bar->remove_node( ‘page’ );

In short – I want my users to be able to add a product and nothing else.

Sorry if this is as clear as mud, it is all quite new to me. (No link to the site available yet-sorry).

Any ideas ?

Thanks
Mark