I think two things to check first off would be scanner alignment and color matching. I don't know what all is available in Quickshow (QS) as I started off with
the Beyond software. You can bring up some test and alignment patterns that will help identify if there are any potential alignment issues and also help with
setting projection sizes and zones. It's been a few years, but seem to recall a very minor scanner adjustment that X-Laser talked me through on the phone.
Same thing with color. Like
SMPTE or
PAL color bars. For color you can map them side by side and compare the color palettes. You can also make some software adjustments
to the color mixing, but if there is a problem it's best to
send back to the lab. I didn't notice this until I started mapping an animation over both projectors mapped
side by side for a wider single projection. Ended up sending them back to X-Laser for adjustment, quick
turnaround, and they came back just about dead even.
Probably preaching to the choir...remember to submit a variance request to the FDA/CDRH, X-Laser will also help you do that and also set up reminder for your
annual report requirements. If you haven't seen them there are also some good blogs:
https://www.photonlexicon.com/forums/ and
https://forums.pangolin.com