Exact same issue with Windows. It works for awhile but as soon as I use sslstrip or any of the other features it stops providing Internet to the client. Default routes are there but it doesn't route anything. I have tried resetting to factory, reflashing, etc. It has to be something with this version of the firmware. It even eventually stops if I just use the MKV as an access point and don't do anything with clients. Runs for about 20 mins and then it stops routing, reboot and it's back for about 15-20 mins and then stops working again.
Definitely frustrated. Hopefully somebody can figure out