Automatic Tranny Downshift

I've got a question about the shift points on a TCU for a 91' Stealth. It doesn't downshift to 1st gear unless you're at a complete stop.

Background:
Several years ago, my car stopped shifting. The problem was determined to be the TCU (there was something visibly fried on it). The TCU was replaced and it would then shift normally. I did notice that when coming to a stop, if I didn't stop completely it wouldn't downshift to 1st gear.

I did find a thread over on 3si where a few reported the same thing and it was deemed to be normal since downshifting to 1st apparently isn't necessary if you're going 5-8 MPH. However, I find the behavior somewhat annoying -- I find myself hitting the gas harder just to get it to downshift so I can accelerate normally.

I'm not sure if TCUs are the same across all years, and I don't know for sure what year the replacement TCU came from. The only reason I noticed the behavior is because my old TCU didn't do this. Would the shift points have possibly been different in later model TCUs or is it possible to adjust the shift point so I don't have to be stopped for it to downshift to 1st?

Thanks