[Hummingbird pro] Hummingbird destroyed some of my sites


I have issues with Hummingbird pro plugin. A few days ago I noticed that sites box4all.eu, skiplet.hr, dolcetti-soljice.rs are not displayed right (sites were broken) so I purged cache and after taht everything was ok. That also happened a month ago, but today skiplet.hr and box4all.eu were completely destroyed even after purging cache.
I have disabled Hummingbird on these websites and they are displayed correctly now but much slower than before.
Plugin is still installed on dolcetti-soljice.rs and that site is working properly at the moment.

How can I / we fix the problem?