If the listings are in idx_link_temp and not in idx_link then one of two things is happening.
1) They need to be approved
2) The database structure for idx_link is incorrect.
Go to the admin panel - database - query and run the following
alter table `idx_link_temp` change `spam` `spam` char(1) NOT NULL default '0';
Code:
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Yes it is telling you to just add that into that line.
If you're still having issues after this then send me your indexu login and phpmyadmin/control panel login to support