When I write square kilometers (km2), and mark the 2, click on the superscript icon I cannot get out of superscript mode unless I write some additional text before I go back and make the 2 into superscript. It has to be text and not just space.
"... km2 was ..." - No problem when making the 2 into superscript and continue writing.
"... km2 " - In this case I can make the 2 into superscript but can not get back to normal text. Clicking the superscript icon makes me loose contact with the paragraph!

ver. 1.0.33-11
os x 10.10.5

It would be nice to have a shortcut key for superscript and subscript because I use it quite frequently when I write.