You can access Options by going to TextExpander >Profile> Preferences > Options.
Capitalize new sentences
Check this box if you want the first letter after a period and a space to be capitalized automatically.
If two capital letters are typed at the beginning of a word and a third lower case letter is typed, the second letter will be converted to lower case automatically (unless Caps Lock is on).
Eliminate at sentence start
Corrects double capitals at the start of a new sentence (after a period and a space.)
Eliminate at word start
Corrects double capitals at the start of a new word.
Do not correct
Turns off this feature, all double capitals are left as is.
You can customize which applications capitalization correction works within.
By default, capitalization correction is enabled for all applications.
all applications except…
Excludes specified applications from capitalization correction.
only these applications…
Includes only the selected applications for corrected capitalization.
Show Available Applications will show you a list of the applications in which TextExpander can correct capitals.