I can't help with any debugging info, because I still don't get how to create it but I am having the same issue as itsskin.
You should see it in the CC application manager/installer or whatever they call that program. Just click 'install' (like you would to install any other CC component, like Ps, Ae, Pr, Sg, Dw, etc).
I also noticed that Bridge is seems very unstable/unresponsive since the iteration of your script with gradient ramping.
Strange, does it still happen without the script loaded? Can you reliably reproduce it by loading this version of the script vs. the old version?
Okay, let me call it average brightness of each frame.
Technically it's not the average, but the median (or some other percentile of your choosing, median is simply the 50th percentile), which is much more statistically robust than the mean. Notice how the median is the same between the two different statistical distributions on this graph, while the mean and mode are different (a histogram is a type of statistical distribution)

I f I am not mistaken if there is flicker between keyframes, the algorithm evens that out - no matter what, especially with multiple passses.
With my proposed method, it would just reduce the flicker leading to a more natural result. This is important when there are clouds blocking the sunlight and the exposure decreases significantly, for a natural result one would like to have a darker image in the shadow, but not 3EV darker as it was in reality.
Your two different parameters are exactly the same thing in terms of this algorithm. You can either correct the exposure completly to the target or not by some amount. Change this by adjusting the coefficient I mentioned. Make it smaller. 2 / log(2) is the best estimation of the ACR black box that I've found, it would represent 100% deflicker (or at least as close as we can get by guessing). 1 / log(2) would be like 50% deflicker. 0 / log(2) would be no deflicker at all.
Would it be possible to create snapshots of the recent .xmp data? If I decide to alter the settings but want to keep the old ones aswell it would be nice to back them up with a right click.
If that is possible, what do you think of the idea to create a folder with the .xmp files and implement a dialogue where one can to load stored sets of .xmp files?
That would be handy to try and compare different developing styles quickly.
Yes, that should be possible assuming Br always uses the sidecars and doesn't ever store the metadata directly in the files, which has always been the case in my experience.