Comment 2 for bug 1238197

I just realized, that the following is already available with version 1.0.1 ;-)

app = os.path.join(r"\\tsarchive", "Storage", "Timeslips", "Installations", Settings.tsVersion, Settings.tsBuild, "setup.exe")
result = run('start /i /b "%s"'%(app))

result contains the textual output, that would be seen if you run the command on commadline

the first line might contain
*** error ***

if the trial to run the command returned an error (e.g. program not found)

generally:
result = run(cmd)

where command contains a string as you would have written it on command line, means correctly quoted, what has to be quoted on command line.