Cubasis VST 2.0 won't assign separate inputs from Tascam US16x08 unit's multiple channel outputs

My first time here, hello everyone…
VST shows 8 green lights on under “inputs” (16x08 sends 8 individual stereo or mono outs via USB, so this part is working). VST Channel Mixer will not allow selection of (can’t click on) “IN” at the top of each strip to assign inputs 1 thru 8 like you’re supposed to be able to do. Essentially, Cubasis can’t recognize and separately populate channels 3 thru 8.
At the bottom of the master fader strip on the mixer, “OUT 1” shows. This can be changed to OUT 3, 5 or 7 after clicking on and off the green input lights. Sometimes, clicking these asks if you want to remap buses.
Other things I’ve noticed: Cubasis VST software somehow deteriorates over time… It’s lost some other capabilities and buttons: monitor buttons can’t be clicked on/off… some automated settings change slightly. I know it’s quite old, like 20 years. I run it in winXPv3 compatibility on a computer that’s running win8.1.
My processor is 1.8Ghz and can overclock itself to 2.5Ghz when needed (Tascam US16x08 requires 2Ghz) but this shouldn’t be the problem.
The Tascam unit uses USB 2.0 for interface - is this newer than Cubasis VST 2, thus creating the problem? Pretty stuck here, fully miked drum kit ready to go! Thanks, people!

Oh, nice, it is interesting