In current release (1 Beta 6.31) you have to select
whole line or go to the start of the line if you want
to make it a comment (to put % sign in front of the line).
I think it would be much better if you can make a
comment no matter where in the line you are currently.
Scite (based on Scintilla) works like that
The other feauture which would be nice is duplicating
lines. For example, when you're somewhere in the line,
you press CTRL+D and it duplicates this line. This is
taken from Scite as well.