Dr. Saxton wrote:This is a good query.  The hyperdrive range is not an error.  As the 
nautical name implies, a "shuttle" is not meant for long-range travel. 
This kind of ship shuttles people between nearby ports or between a 
mothership and a port.
Palpatine's Theta-class shuttle in ROTS has approximately the same 
capabilities as his Lambda-class shuttle in ROTJ.
  * In ROTJ, he voyaged from Coruscant to the Outer Rim aboard the 
Executor.  He used his shuttle to transfer from Coruscant to Executor, and 
then from Executor to the Death Star 2.
  * In ROTS, he used a Theta-class shuttle to transfer from Coruscant to 
another large mothership (unseen in the film), which jumped to Mustafar. 
He takes the shuttle down to the surface to collect Vader, and returns to 
the mothership.  This ship then jumps back to Coruscant, etc.
.......
The same is true of the V-wing fighters that escort the shuttle to its 
landing in Imperial City.  They deploy from the naval vessel.  A manned 
fighter that size is incapable of hyperdrive, and needs to ride a larger 
ship or hyperdrive ring.  No amount of expense can avoid the physical 
limitation.
The visual dictionary was wrong (confused) on that point.  This is 
pardonable because all the writers are buffeted by suggestions from many 
quarters (some of them ill-informed) and the manuscripts need to be 
finalised months before the film is finished!
If (off camera) any of the V-wings _had_ jumped in parallel to Palpatine's 
flagship (rather than riding it) then they must have used hyperdrive 
rings.  This is a redundant point; I believe there wasn't any such jump 
filmed (let alone filmed & cut).  I specifically sought confirmation from 
LF when I was writing ROTS:ICS.
[...]
PS:  I was never given any reference images for the appearance of 
Palpatine's flagship in ROTS.  That subject wasn't ready at the time when 
the ROTS:ICS manuscript deadline.
If I were forced to guess, the ship is probably something like what 
carried Palpatine, Vader and Tarkin on their inspection of the Separatist 
"Great Weapon".  The curved bridge interior seen at the end of the film is 
inconsistent with all the surfaces of the Venator destroyers (which only 
allow for rectangular bridge structures).
Since the exterior of this ship never appears on-screen, I guess that it's 
now unlikely to be developed and shown in any medium.  

 If we're 
extremely lucky, someone might include late-developed concept art on the 
DVD extras.  With few constraints, apart from KDY architecture, I imageine 
that the ship could be like any of the large multi-mile vessels we've 
already seen in the literature.  It should be whatever is the Clone Wars 
equivalent of the Executor; maybe a Mandator-II.