If you set the Genie to Record a Season or Series from the Menu (There is a SW issue) It will Record all Shows either broadcast live or from On demand (internet) so It's Possible depending on the Channel -That you were watching a Downloaded show and (example) NBC Shows Downloaded will Disable FF & RW on content.
Selecting a Show from the Guide (and) Pressing the Record button twice will insure it will only record the Series when Shown over Sat (Live) Allowing FF & RW to be Done.