If I'm downloading or efileing Turbotax, with a slow connection or is interrupted can I resume the download at a later time or day at no additional charge or problems?

Yes ... but I would start the download again from the beginning to avoid any errors. 

There is no charge to efile.  The Online fees are to prepare the return.  Yes if your efile times out of is Rejected you can try again no charge. 

Thanks for the fast response.  What about while I'm trying to download Turbotax and the internet drops out?  This happens frequently.

Thanks again 

As I said ... if the download is interrupted you may need to try again from the beginning ... maybe find a place where you have a better connection.