I've spoken to the local Minolta rep about this issue and he said
that to use slave units for studio lighting the "work-around" is
as follows:
1. using the 5600HS (D) flash or earlier model flashes such as
5400HS, 5400Xi, 5200i, or 4000AF (some of the earlier models will
require the FS1100 hotshoe adapter) set the flash into MANUAL mode.
Next, manually select the lowest power setting available for the
particular flash you are using such as 1/32 power level or 1/64
power level.
You were told by Minolta rep that D7 works with older (no "D")
flash units or were just discussing in general?
I'm afraid the only flash units that work with Dimage 7 are the two
"D" units (3600 and 5600) and the two macro flash units. I've
tested 5400 HS with D7 and it was really doing crazy things. Manual
power setting did not work at all. The flash immediately switched
to TTL/automatic mode when mounted on the D7.
But that's not all... When I took a picture, I got the same result
as by pressing the test button on the flash. Depending on the flash
setting, modelling flash on/off, it fired a full power burst or a
rapid series of low power bursts (modelling flash). ADI/pre-flash
setting on the camera had no effect.
However, aperture priority mode seemed to work OK. I was able to
get a decent exposure by stopping down the lens - if the subject
was not too close (f8 is a real problem here).
Marko