If you come across any please post about it in this thread or in your own!

Without spoiling too much, the boss in Deep Cavern disappeared after defeating parts of him and never reappeared. Leaving the area via exiting to main menu does not fix the issue. Resetting the enemies did reset the boss and focusing on the boss itself allowed me to pass it. Acquiring the swim upgrade for wyvern form does not currently work. Tried backing up like I do with the boulders because being too close causes them to become invulnerable, tried every button press I could. Nothing. ...

No way to change layout that is going to give my hands cramps having to hold that button down all the time lol

It is possible to use the wyvern's swimming ability and escape the map in some places using the "waterfalls". Here's a screenshot: https://steamproxy.net/sharedfiles/filedetails/?id=2970016180 Also, the water in the waterfalls appears to be climbing upwards....

or anything close to that.