1's and 2's Complements

In a thread from 2009, georacer stated:

I could say to you to the least that in a base X format, you can find complements from 1 to X of any number, always given the digit size of the number. The complement in regards to N of a number Y is NNNN-Y
For example, in base 2, the 2's complement of 0100 is 10000-0100.
In base 2 again, the 1's complement of 0100 is 1111-0100.
In base 10, the 5's complement of 0023 is 5555-0023.
In base 10, the 10's complement of 0023 is 10000-0023.

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I'm somewhat confused in terms of the definition of complement, which is something like:

The two's complement of an N-bit number is defined as the complement with respect to 2N; in other words, it is the result of subtracting the number from 2N, which in binary is one followed by N zeroes

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Question: I'm confused by the fact that for base ten, the sum of a number and its complement is 1 + n 0's,
but there does not seem to be any such equivalent statement that would describe what happens in the 5's complement (for base 10) quoted above: i.e., 5532 + 0023 = 5555. Why not 55555 or any overflow? What fundamental part of this don't I get?