coregistration GUI icons

I get the following GUI when during coregistration:

If you notice carefully, the icon next to "Omit" is showing exclamation mark and the "-" and "+" sign that is expected for delta X, delta Y etc is missing. Here is my sys info:

Platform:      macOS-10.15.6-x86_64-i386-64bit
Python:        3.7.4 (default, Aug 13 2019, 15:17:50)  [Clang 4.0.1 (tags/RELEASE_401/final)]
Executable:    /Users/mainak/anaconda3/bin/python
CPU:           i386: 4 cores
Memory:        8.0 GB

mne:           0.23.dev0
numpy:         1.17.3 {blas=openblas, lapack=openblas}
scipy:         1.3.1
matplotlib:    3.3.2 {backend=MacOSX}

sklearn:       0.23.2
numba:         0.45.1
nibabel:       3.1.0
nilearn:       0.6.2
dipy:          1.1.1
cupy:          Not found
pandas:        0.25.0
mayavi:        4.7.1
pyvista:       0.26.0 {pyvistaqt=0.2.0, OpenGL 4.1 INTEL-14.7.8 via Intel(R) HD Graphics 6000}
vtk:           8.1.2
PyQt5:         5.13.0

Furthermore, a couple of usability comments:

• "Guess subject from name" should be unchecked by default? The issue is if you have already checked the subject, and then you load the MEG file, it changes the subject. So it becomes annoying to replace it again.
• It might be helpful to have the fiducials below and above the surface in different color? Not sure if it's worth the effort but mne_analyze does this ...

No file, test, or code entry point is named. Start by reproducing the coregistration GUI on the reported macOS/PyQt5 setup and locate the code responsible for the Omit and delta-value icons. Done should address the missing icons and consider the reported subject-selection behavior; the fiducial color suggestion is optional.