On each edited i had some issues to fix (listed below) and removed the unused envelopes, because why not.
I think its important that the teeworlds standard maps have all issues fixed, since they are probably often used as templates for maps (or appended to other maps).
fixed irregularities:
ctf3: corrected game layer name, all 4 envelopes were unused, had invalid utf8 in name
ctf4: corrected game layer name
ctf6: corrected game layer name
dm6: corrected game layer name, all 4 envelope...