Hello again! We have now released a patch which covers most of the known bugs in the game, such as the screen staying black after the tunnel section ends, so if you'd like to play it, the game should now be playable all the way through.
We apologize for the bugs the game had and for any possible future bugs we still haven't found. Since it's the first proper game we've released, things like these are bound to happen.
Also, regarding the tedious walking in the area near the watchtower...
Instead of allowing the player to run at the watchtower, we are looking into alternatives such as reworking some of the progression at that stage of the game to better fit the game as a whole and make it less tedious.
Thank you for your time and effort in reporting these bugs, it has helped a ton in finding them!