Auto create settings page for each custom post type

I`m creating a website in which a custom post type is created for each created category. This works great, however i wish to add a settings page to each custom post type section, holding unique values for each post type.

i have it set up like this:

add_action('admin_menu' , 'add_site_settings');
function add_site_settings() {
			$tax_terms = get_terms( 'category', 'orderby=count&hide_empty=0' );
			$count = count($tax_terms);
			 if ( $count > 0 ){
				foreach ( $tax_terms as $term ) {
				if($term->slug!='uncategorized' && $term->slug!='' ) {
				 	add_submenu_page('edit.php?post_type='.$term->name, 'Theme settings for '.$term->name, 'Theme settings', 'edit_posts', $term->name, 'plugin_options_page');
				}

			}
		 }
	}

	function plugin_options_page() {
		?>
	<div>
	<h2>My custom plugin</h2>
	Options relating to the Custom Plugin.
	<form action="options.php" method="post">

	<?php settings_fields('plugin_options'); ?>
	<?php do_settings_sections('plugin'); ?>

	<input name="Submit" type="submit" value="<?php esc_attr_e('Save Changes'); ?>" />
	</form></div>
	<?php
	}

	add_action('admin_init', 'plugin_admin_init');
	function plugin_admin_init(){
		register_setting( 'plugin_options', 'plugin_options', 'plugin_options_validate' );
		add_settings_section('plugin_main', 'Main Settings', 'plugin_section_text', 'plugin');
		add_settings_field('plugin_text_string', 'Plugin Text Input', 'plugin_setting_string', 'plugin', 'plugin_main');
	}

	function plugin_setting_string() {
		$options = get_option('plugin_options');
		echo "<input id='plugin_text_string' name='plugin_options[text_string]' size='40' type='text' value='{$options['text_string']}' />";
	} 	

 // validate our options
	function plugin_options_validate($input) {
		$newinput['text_string'] = trim($input['text_string']);
		/*if(!preg_match('/^[a-z0-9]{32}$/i', $newinput['text_string'])) {
		$newinput['text_string'] = '';
		}*/
		return $newinput;
	}

This creates a settings page under each custom post type i creates, however, it`s the same for each custom post type, so the value i enter in CPT1 will also be shown in CPT2.

Its needs to be dynamic, i cant create all functions in advance (that would be a solution) so each time a category is added, a new CPT needs to be added with settings page.

Problem is, i can`t pass variables to plugin_options_page, i tried to trick it with a $_GET variable but no luck. Maybe a global would help, but how and will it be safe?

Any briljant ideas?