WordPress.org

Does this plugin allow complex adsense management?

No.

I am updating an older version of the plugin. Will it still work?

The method for displaying ads changed in version 1.2. The old style will continue to work in this version, but it highly suggested that you update all the adcode in your content to the new method.

An easy way to do this would be to install the find/replace plugin (http://wordpress.org/extend/plugins/search-and-replace/) and update all your old tags. E.g. Find and replace it with [wp_ad_camp_1].