Enable Lightbox Gallery is set to Yes on the Settings tab. Is that what you mean?
I was really worried you were going to say that your plugin is not compatible with either PowerPack or UABB. I am not sure how much of this site is built with the PowerPack, but I will test this on a different install with PowerPack turned off, and report on the results.
But if you knew about his have you not reached out to them?
I will let you know my findings without PowerPack active and then go from there. But it sounds like I am going to have to reach out to their support and in the mean time say bye bye to using PowerPack on this site 🙁