I have created an issue #301112: form loses data when submitting already and am posting here only to get more attention on this issue. I am totally at my wits end and so seems everybody else who has kindly looked at the issue.

I have written the module to create nodes of a new node-type that in the first step ask for address info, then asks google to provide its coordinates, then in the second step lets the user place the marker on the exact location, and finally submit it. However, after/during/shortly before submitting, the data of my form is lost.

What am I overlooking in D6's form api? There must be something I am forgetting! Do I need to copy some values in this $form_state data structure, and if so, which hook should I implement for doing that? Do I need to use callbacks rather than hooks, and which ones?

Please do take a look, I posted the complete code of the module with #301112: form loses data when submitting.