Wild_Mortimer, I like the itch's theme for this game and my next thought being a "+" in rating because it's available as browserversion.

When starting the game:
Cool text-style/font-type, I'd prefer the "play..."-lines in e.g. ust small letters than capitals there e.g. and the main-title just in big letters like it's already coded. The hovering on "play..."-menu looks nice as effect, like from light to darkgrey in colours. I think both graphics sound interesting because the crab being more handdrawn than the awesome fire-parts of he second image.

Menu: play from checkpoint. Even I never played it yet, just "testing" when the codes reveals there:
It actually loads a sequence, the left side ...red font on darkbluish background with white pixels looks rather less awesome in visuals, maybe more bright text-font and less intense background, or blurry "walls" could fit better there? Also the in-game background could be e.g. bit different than the "outside" walls, which could be like the adding "blurry effect"-suggestion. I'd also adore a e.g. mirrored version of the single images than noticing the same icon next to each other in x & y-lines / horizontal and vertical repeat.

in-game controls:
Looks look in visuals. I like that the right-click won't get the common menu appearing. left-click + dragging, would be even more perfect if my center-spot would be the crab, while currently it seems to be based on my pointer's location?

my device:
win8.1-laptop, basilisk browser.
Having to minus-zoom once, for the full view. Do you plan possible itch's fullscreen-button adding to your game, not sure if scrollbars sound useful (so far I don't think so).

music:
In my opinion it somehow don't fit to an adventure game? Sounds more like a lullaby-version for visual novels (ambiente-themed, no horror-scenes).

text-aesthetics:
Probably just a small detail ...text varying between verbs in big letters to small ones, I'd prefer them e.g. only in small ones, if that sounds easier for coding, while it looks optical more smooth than random words starting with a capital letter.

first level: "go forth - king", maybe there could be the same size, also cool that it differs from the control-keys' colours and maybe another placement could solve the issue of almost overlapping in fonts there?

freeing caged crab: I was moving my protagonist, typing reviews here, back to game-tab ...now my crab isn't on screen? Timer's still counting, zero deaths but how o get my crab disappearing? Maybe I just dragged it off-screen somehow?

pause-nav:
"you have paused", would be cool in x2 less big letters, I like the music notes' icon and slider's colours.

Just clicked pause, start from checkpoint. Got to the same lv & dragged that crab on purpose off-screen. Could I suggest: maybe a "bounce back"-option would be cool if releasing mousebutton. Or optionally: hovering in that direction and a text fades in temporary which states like "you'd get your crab off-screen if aiming there, still sure to continue?", while the second option will still change nothing optional, needs a restart anyway. I guess the first one being probably easier to implement in coding?

I like the moving with dragging than keyboard-buttons, sounds unique/creative & maybe the narrow-path could be  bit bigger to guide my crab through it?