Hi, bug reports here are perfect, thanks! I actually discovered this exact same issue only a fortnight ago and put it on my list. I'll bump it up 🙂
The underlying cause is actually a recent Apache bug—see here. Indigo v1.0.0 included Apache 2.4.62 which unfortunately contains this bug.
There's nothing practical we can really do to work around this. What I can do however is implement a warning in Indigo so that you know it's not going to work if your path has spaces. I acknowledge it's not a fantastic outcome, but I'm not really sure what else we can do, other than hope they fix it upstream soon.
Please do let me know if you have other ideas for handling it better than what I'm proposing 🙂