TYPO3 Core

I can confirm that the second issue appears on TYPO3 v12.4.9, and with "customsubcategory".
The label is not used when there is no empty line after the comment.

The reason for that problem is that the comments get attached to the following node by the AST parser.
Category labels are only looked for in the root node comments in v12, while at least in v10 we could declare categories everywhere.

Broken:

# customcategory=test=Test
test {
    # cat=test/color; type=string; label=Color
    color = orange
}

Works:

# customcategory=test=Test

test {
    # cat=test/color; type=string; label=Color
    color = orange
}