One-off characters [8 chars of raw binary data] print unnaturally.

Or I may not understand this feature.
I was aware that "\^.00000000" would print nothing.

The 0 character actually won't produce an empty line. In hex, you'll need to use 00, and if you're using each character as a byte value, you need to use \0. For most of the rest of the characters, my CHR Printer tool https://www.lexaloffle.com/bbs/?pid=84578#p makes outputting them easy, but due to issues with control codes it doesn't currently support chars 0-15.

Ah, I see, I understand!
The input value needed to be specified as a character code[CHR(0~255)], not as a number from 0~F.

So if I want to output a blank character, I can do so by specifying ?"\^.\0\0\0\0\0\0\0\0".

Thank you! @JadeLombax