I've been trying to get the new TU out the door but stumbling blocks have been set in my way. As a result I needed to push this, the older version of TU, with AppleTV 4.3 (4.2.2) support.
Note that you need to go into Advanced options and uncheck the box that says 'Request SHSH from Cydia' and then click 'Apply Changes' in order to save your SHSHs. This is because Cydia is not able to act as a proxy for your SHSH signatures.
I'm working on the new TinyUmbrella which will have many features that you all have been waiting for. Bear with me :)