ERROR: ExecuteAsync

I have a strange issue, hopefully some Kodi python gurus can help with.
My addon has a setting in the settings.xml which calls a script that is included in my addon:

Code:
<setting visible="true" label="Run the Wizard" type="action" action="RunScript(special://home/addons/plugin.program.iarl/resources/lib/run_iarl_wizard.py)"/>

I’ve tested this for as many installations I can and it seems to work for the most part. Some users say ‘it doesn’t work’ and have provided a log which does appear strange to me (summarized for clarity on system type and the area I’m focusing on):

Code:
NOTICE: Starting Kodi from Debian (15.2 Git: (unknown)). Platform: Linux x86 64-bit
NOTICE: Using Release Kodi from Debian x64 build
NOTICE: Kodi from Debian compiled from 15.2+dfsg1-3ubuntu1 by GCC 5.3.1 for Linux x86 64-bit version 4.4.6 (263174)
NOTICE: special://home/ is mapped to: /home/xyz/.kodi
ERROR: ExecuteAsync - Not executing non-existing script special://home/addons/plugin.program.iarl/resources/lib/run_iarl_wizard.py

The script clearly exists in the addon folder and works for most systems. The log above makes me think Kodi is looking in the wrong place for the script though. Or does ‘ExecuteAsync’ point to some other problem?

Thanks!