For COMs, is requiring a non-native library allowed? If not, then I'd suggest going with COMs not being allowed.
The reason is that what is native to my machine may not be native to yours. Not that its allowed, but a decent example is windows native MSXML. Some machines have v2, later versions have v3, win10 has v7. Each has different interfaces, quirks, etc.
And could you clarify requirements on brackets, as you made no mention of them. Are we allowed to have unclosed brackets?