While investigation this problem, I found a minor bug in the selection of baseline time points, leading some time shifts to skip one of the baseline time points, giving slightly different results when testing for significance.
I fixed it : Bugfix: Epileptogenicity baseline time selection was not robust to ti… · brainstorm-tools/brainstorm3@b2a10bc · GitHub
@odavid Maybe you'd like to report this to the ImaGIN repository.
However, I could not find a way to reproduce the behavior you described here. I used the Epileptogenicity tutorial dataset, seizure 1, compute the delay maps for -2:1:2 and shifted it by -4s and +4 (both the Time vector in the Onset files and the Lacency option in the process). I obtained exactly the same maps, displayed exactly in the same way.
Can you start by recomputing carefully what you did to make sure you didn't to any manipulation error?
Could you illustrate this on the Epileptogenicity tutorial dataset? (if you still have it on your computer)?
Is this an error in the delay map files (you can check the actual values by right-clicking on the figure > Get coordinates) or a colormapping error (the time values are correct but incorrectly mapped to the colors)?