Mostly with setup and configuration. Configuring it to work the way I expected required a lot of digging through documentation/code/blogs/fudging around. I don't like it when I have to do that, for a number of reasons -- a. I'm lazy and I don't like spending a lot of time doing upfront configuration, b. when something doesn't come with sensible defaults pre-configured, I assume I'll do something wrong and it'll have non-obvious but bad consequences.

I had this problem with django-compressor as well (but more with configuring 3rd party asset compilation). I usually recommend people use webassets via django-assets. It's easy to configure and very feature-ful.