The only way you could do this would be to upload them to the Roamio first, then use the online.tivo.com website to transfer them from the Roamio to the Bolt. Not really ideal, but if you're just doing it occasionally then not that big of a problem.
If you want to watch stuff on your PC frequently then you should look into using Plex instead. It'll stream from your PC to your Bolt.
Alternatively you could revert the Bolt to the old UI. But that will delete all your recordings and passes. You can back everything up using pyTivo and kmttg first, then restore once you're on the old UI, but not everything can be transferred. Some premium shows and certain other channels, depending on your cable company, are protected and can't be transferred to a PC.