Hey, thanks for trying the demo, glad you like it. :)
Maybe I should have made the end of demo text a bit easier to see. ;)
So, the boss has gone through some big changes since the demo was released so I can't really comment much on that right now since it's not exactly the same anymore.
I do however agree with the randomness, some of this has been improved upon in this new version of the boss with more opportunities to actually hit it.
More on that subject should exist in some of my recent devlogs.
As for the enemies in the ceiling, they have also already been changed to be more noticeable.
And everything ledge grab related have been improved and the issue you were having basically doesn't exist anymore. Left/right no longer lets go off ledge grabbing by default, there is now a horizontal momentum boost when ledge grab jumping to allow you to jump further, you can now aim diagonally with the d-pad if you enable a setting and likely some more changes.
There is also a new accessibility setting called "large font" which is self explanatory.
Hopefully I can get a new demo update out soon so new people won't have to experience these issues anymore.
Anyway, thanks for the feedback, even though pretty much everything has supposedly already been fixed. ;)