tushev.org

As you know, Last Update Module for Joomla! processes not only built-in core types, such as contemts, weblinks etc, but as well some other extensions - VirtueMart, for instance.

So, if you want to make Last Update Module support other extension, you can...

...You can send a link to the extension to the author and possibly it will be included in the next release.

...But if you want this to be done more quickly, or you're asking about a commercial extension, do the following:

1. Open your database management tool, eg. phpMyAdmin
2. Open your database
3. Find the tables related to your extension. For Virtuemart these are all beginning with vm_ (totally 53 tables).
4. Among them find that contains the necessary information (last modification dates). In our example it's jos_vm_product. This is the first part of necessary information.
5. Open Structure page. Save the results (better as a screenshot)
   
   Corresponding query: DESCRIBE jos_vm_products;
   Find the fields that are related to modification dates. In our case, those are cdate & mdate - containing creation & modification dates each. In other cases names may look like date, modified, created, imgdate, lastupdateon, ...
6. Open Explore page. Scroll it to the necessary fields, save. (better as a screenshot)

Send all these data (table name, structure, examples) to the author.
After a while, you'll receive new version of  Last Update Module for Joomla! that supports your extension. Test it, and then, if everything's ok, this version will be published.