After enabling screen lock and copying a .p12 key + certificate bundle onto the sdcard, security -> Install from storage does not work. It does not give an error, just flashes the screen.
If you try and install the user cert via downloads in Chrome, it gives the error: no certificate to install.
Any ideas, debug techniques for Android settings / CertInstaller.apk or suggested work arounds ? I've tried this in Android x86 Nougat 7.1-r1 and the .p12 installs OK. I suspect a problem is related to screen lock. CA's seem to add ok.