We investigated the case and it appears that this scenario is currently not supported in RadMap. You can submit a feature request in our feedback portal
and we will later approve it and log it in our system. It will be available for voting and the more votes it gets the bigger its development priority will be.
The RadMap internally uses WebClient.DownLoadDataAsync (Uri uri) method and it appears that it cannot work with pack uris. We will follow you up next week if we manage to find a possible workaround.
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