It is confusing with the Joomla 1.5.x versions and the versions of the components. To make it clear - here's a list how everything fits together.
All versions after 2.0.0 of Event Table Edit are native for Joomla 1.5.x. That means you don't have to activate the legacy plugin for the component. Go to download area
The first version of the component were written for Joomla 1.0.13 and later 1.0.x versions. When we recognized that Joomla 1.5 will be the future of the CMS we decided to jump on the 1.5 train and only built versions for this new Joomla. So version 1.2.0 of Event Table Edit is the last version that can be used with Joomla 1.0.x. Go to download area