If you had the old "S-S" cable it should work fine with both the QAM and non-QAM units. As a matter of fact, it should also work with the DSAM provided cable that goes between the SDA-5500/5510 and DSAM units but I can not confirm that, but it would make sense.
The older "S-S" cable was specifically wired to work to the Wavetek standards. Using a standard DB9-DB9 with a null modem just happened to work out on the older SDA, 3-SR and 4040 units but Wavetek always instructed their customers to use the factory supplied cable. With the QAM units this was mandatory.
As for the Stealthware 7.0 and 7.1, I have only worked with the 7.0 with Windows XP. I believe that the 7.1 was a verson that allowed Stealthware to work with Windows Vista but I can't remember exactly.
I do have a copy of Stealthware 7.0 if you need it. I'm always happy to help if I can! It's just good to see that sweep is still being used in the HFC networks!