If I may have one last question. Could you point me to the document(s) or forum threads that talk about how to get events in non-visible HTML tags on which you can trap events like "onchange" to execute different sets of javascript code based on the data received before they are posted to the browser?
you can specify the schema of the table passing an array instead of a null to the table constructor. This way you can provide a schema that is larger than the schema used by the table on the html but you will receive in the callbacks the updates for all the fields.
OR
if you need only not-visible cells you could use a NonVisualTable instead of using an OverwriteTable

all the docs for the web client are available online and in the distribution zip.

(in case you are referring to DOM events instead of referring to Lightstreamer callbacks, you can find the complete list of DOM events on wikipedia)

HTH