Omex 600 Cosworth YB

Hoping for a bit of a steer on this.

Summary of the story so far- Friend of mine has a Cosworth running said ECU. Always complained of a kind of misfire (I'd describe it feeling like you're on a poor road surface) which I eventually found to be a lack of screen grounding on the Crank sensor. Screen connected to ground, all good and car running great. During the initial fault finding process we spoke with Omex who were helpful and they advised the firmware be updated from 0.55 to 0.70. The owner sent the ECU to them, they checked it over and updated the firmware. We went to reload the map and no good. I then found the map conversion process and carried it out but the car would fire up. Again support from Omex and the car now runs- although I have had to manually transpose ALL settings from the original file.

Now this is where I need a steer- the misfire type issue is back and the manual isn't clear on setting the 2x timing filter settings (MX Time) and I don't want to keep blindly trying different settings so I'd appreciate knowing what each does or at least the correct method finding the right setting as Omex haven't been clear. I will caveat that I do need to fine tune the Hi-Lo signal gains too.

Secondly injector scaling. He is using the go-to Dark Greens which I believe are 380cc connected via ballast resistors.

Lastly Omex commented that the MAP scaling hadn't been set so instead of reading -100 to +250 (I think) it was up to 0 (or maybe -100) to +100 and the Ign and Fuel tables were scaled to this.

Any tips on calculating or setting the scaling- or is it purely down to tuning with the Wideband to see what appears "right"?

Keep in mind the car was running "OK" for 10+ years and following the addition of the screen to the crank "the best it ever has".

Annoyingly the gritters are out for the next few weeks, plus a lockdown in the UK, so we can't currently play and see where we end up.

Thanks :-)