The Preferences window (in Komet -> Preferences…) is the first place to check for user settings.

Common settings regarding fonts, warnings, and software update checks can be found there.

Automatic spell checking, spell correction, and text replacement settings can be toggled respectively from the menubar via:

Edit -> Spelling and Grammar -> Check Spelling While Typing

Edit -> Spelling and Grammar -> Correct Spelling Automatically

Edit -> Substitutions -> Text Replacement

These are also accessible via right clicking in the editor. By default, the automatic spelling correction and text replacement settings respect the system default settings in System Preferences.

A fun set of themes and translucency options can be tried out in the View menu.

Since version 1.0, the default theme is Automatic which uses the Plain or Dark theme depending on your system's current light/dark appearance.

User default flags can be passed for more advanced usage. For example, to use Komet for altering a configuration file one may invoke:

/Applications/Komet.app/Contents/MacOS/Komet configuration.txt -ZGAssumeVersionControlledFile false -ZGCommitTextViewContinuousSpellChecking false -ZGCommitTextViewAutomaticSpellingCorrection false -ZGCommitTextViewAutomaticTextReplacement false

For this one session, this example overrides and disables a number of conventions usually used to help editing commit messages. Note the default flags must be passed after the file argument. A full list of defaults, albeit undocumented, can be found in the UserDefaultKeys source.

The ZGAssumeVersionControlledFile default is new to version 1.0.