Hello @matigka,
Thank you for contacting us and your question.
The google feed manager plugin only supports 100 products. The premium version will support product feeds with unlimited products. If you are running the Premium version and you are still unable to have more than 100 products in your feed make sure you have upgraded to the premium version with the following steps
Step 1. Create a back-up of the feeds you have created before in the settings page.
Step 2. Deinstall the free feed manager plugin from the plugin page.
Step 3. Install the premium product feed manage plugin like any other plugin
Step 4. Enter your license key and validate.
Step 5. (ecommerce only) install the google channel in the channel manager
Step 6. Restore the feed back-up in the settings page from our plugin.
Step 7. Regenerate the feed(s)
?Step 8. Ctrl +F5 to empty your browser cache.
If that did not help you please send me an email at auke[at]wpmarketingrobot.com