Since 2020-10-29, an API key is required to download data.
Your token can be found under your account settings (see screenshot)
On the settings page, copy the API key if present, or generate a new one. Enter it in the Funnel connect dialog.
If you're having trouble finding your API key, your Seznam contact will be able to help out.
Pick Campaign, Adgroup, Keyword or Query report depending on your needs.
Pick the currency used for you monetary metrics in the Seznam platform.
If you select "Query" or "Keyword" reports, you'll have the option to "Allow empty statistics". Chose "Yes" if you want stats for all objects regardless of status. Be aware: this can lead to large amounts of data.