I think here is a bug in version 0.4.0.2 on Windows 10.
When pause torrent it is impossible to resume it using toolbar button.
Only works on right click torrent and click "Resume".
This also accurs on 0.4.0.1
Using Halite v 0.4.0.3 on Windows 8.1 Enterprise x64. I can confirm that the Play button in the toolbar does seemingly nothing.
Windows 8.1 Pro user reporting in.
the Play button does not work either.
See #21 (comment) for and explanation of the fix.