Geek,
Gotta love your hack's :P
I think you forgot to drink you coffee and forgot the
" . TABLE_PREFIX . " on line 81 of the /admincp/GAB_admin.php which could cause a problem to those using a table prefix on thier database.
Also would be nice to edit the README file to mention something about the table prefix if not somehow add a code that would check for a prefix when running the tables.
Well done hack, but I want my installer
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Also when I place the $GAB_ad1 variable on the navbar template I can not see it on forumhome, the forum index page.