I just tried it under OSX and the same bug seems to exist:
Open sublime on windows or osx (and probably ubuntu -- I'll try this afternoon). Make the layout two columns and put an empty file in each column.
In the first column type "hello", in the second type "there".
First try single clicking on "hello", then on "there", then back and forth. The focus and cursor changes between the views as expected.
Now try double clicking on "hello". Then click on "there". The focus changes which is good. Now click back on "hello". The cursor remains on "there".
Instead of double clicking, you could have also selected it with the mouse.