Works as expected on 10.15.7 with default BaseSystem.dmg, but does not work with custom BaseSystem.dmg?

[NSExceptional]

First of all, awesome work on this script. Super useful and insightful.

I followed this tutorial for building a custom BaseSystem.dmg, as I want to add some files to the recovery partition. Namely, I want to add /private/var/root/.bash_profile so that I can add some aliases to the recovery shell.

In a nutshell, I took BaseSystem.dmg, mounted it, cloned it as read-write, modified it, and converted it back to compressed. Then I tossed it over the original BaseSystem.dmg in Install macOS Catalina.app and ran the script. The script ran with no errors, but when I boot with ⌘R, it takes me into internet recovery. If I reboot and run the script again with the original BaseSystem.dmg, recovery mode works.

I'm wondering if anyone can help me out here. I realize this probably isn't an issue with your script, but with whatever it is I've done to create my custom BaseSystem.dmg. Anyone know what might be wrong?