The test file is obviously OK.
I could create hatch and solid fill with LibreCAD 2.0.7-45-g00c66c0 on both, the circle and the square.
But the tool seems to be broken, in latest version 2.0.7-335-g3e7b56e hatch and solid fill doesn't work anymore.
We have to bisect this to locate the buggy commit.
Thus, it's not your fault. If you can build from source, you may checkout an older commit, e.g. 00c66c0 or wait for removal of this bug.
Armin
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