After reviewing the information provided on Unicraft's V-4 page, I
took a look at the dimensions of the missile and the ramjet engine,
which is definately not an Argus or Lorin type.
The Pabst ramjet, however, matches exactly in dimension and
configuration. It had been successfully tested as evidenced by this
1944 photo:

http://www.germanvtol.com/tribflugfolder/5treib.jpg

The question is if the ramjet was good enough to be mounted on the
missile and production of a number of missiles could have occured in
the early months of 1945. The Pabst ramjet was to be used on the Fw
Triebflugel but that aircraft was never built, neither was the radical
Epps Omega Diskus which would have also used the ramjet.
However, the story of the threat to use this weapon against Sweden is
known. Ian Hogg mentions the V-4 briefly in his "German Secret Weapons
of the Second World War"... but gives no clear description of the
missile except to say it was generally thought to refer to the
Peenemunde A-9/A-10 ICBM project. Anyway, a Swedish diplomat claimed
to know all about the V-4 project in 1945 and when Hitler was
informed, he laughed and called the diplomat a conman. Hogg uses this
to discredit the entire project, implying it didn't exist if Hitler
wasn't aware of it.
But I disagree. Hitler is only claiming that the diplomat didn't know
what he was talking about when he claimed to know "all about the V-4".
Missile launch ramps constructed in Poland and the German diplomatic
warning to Stockholm over the V-4 threat contradict Hogg's beliefs.
Anyway, the Russians who captured the launch areas moved all the
German missile testing to N-II-88, Kaliningrad (former Konigsberg).
There, they tested the Wasserfall, Schmetterling, and other captured
missile technology.
It is interesting that a few years later Russia was building missiles
originating from these German designs and guidance systems, although
improved by captured German scientists. It is claimed that the V-4
missile was actually turned into a SAM- the Lavochkin La-219 (V-300).
Here is a pic of that 1949 missile:

http://libraryautomation.com/nymas/Lavochkinmissle.jpg

Of similar dimensions, minus ramjet propulsion. No conclusions there.
The only thing I can think of is that many of the postwar "Ghost
Rocket" sightings in the Baltic (coming from Peenemunde) might have
been either extended range V-1s or maybe appearances of the mysterious
V-4.

Rob