The windows installer (.exe) for version 0.5.15 has an issue where it puts the files for the spell checking in the wrong place. The spell checking still works but the files interfere with the subprocess module so things like Launch and source control commands in the Projects plugin will appear to do nothing.
This can be worked around by removing the following files from your installation path (i.e C:\Program Files\Editra)
* All .py and .pyc files
iconv.dll
intl.dll
libenchant.dll
libglib-2.0-0.dll
libgmodule-2.0-0.dll
This will of course cause the spell checking feature to become disabled.