USB to Serial Adapter - Programs the Stamp but doesn''t work ?

Archiver

Hi all.
OK, I know, the whole USB-to-Serial Adapter thing has been discussed,
but I haven't seen my particular problem... Here goes:
My I-Concepts USB-to-Serial adapter ($28 at CompUSA, marketed towards
PDA users) works FINE as far as seeing the Satmp2 and programming it.
However, when I run a program using serial commands from the PC to the
Stamp, the I/O doesn't work.
I've tried shorting out pins to eliminate handshaking (as described in
the manual), I've tried slower baud, and endless combinations of
8,N,1,none, etc.
The program I'm using is from Stamps In Class - the one that uses
LabVIEW to talk to the Basic Stamp - "LabView Interface for the BASIC
Stamp". The BS code and LabVIEW vi work great through a normal com
port, but not when I use the USB-to-Serial adapter.
I have used this adapter with other programs that use LabVIEW to
non-Basic Stamp stuff and it communicates just fine.
Again, this adapter programs the stamp fine - just doesn't do serial
communications. (?)
Any ideas?