A choice was made here that I really don't understand. As far as I can tell, this is an entry never meant for printing out. The choice of header font, the color heavy design, and the decision to put a bright white on a vibrant blue are all pretty rough for readability. When I scale it to page size, it is basically unreadable. This holds true even on the headers, especially the second page set (spread). For some reason, it seems like there's a noticeable readability difference between the first page set and the second set. I assume it was bolding or something else.
There's a 0% chance I would ever print this out to add to my folder by the sheer volume of blue ink usage alone. If I wasn't using an ecotank printer, it means I would burn down the blue of a cartridge in no time. More importantly, it would be printing the blue and leaving the white blank... which bleeds a little and is going to be just as unreadable in a printed page as it is on a screen. Possibly worse depending on the quality of someone's printer.
I tried blowing up the sizing on my screen and found that I needed it over 100% of a rather large screen to read and it only became sharp at nearly 200%. This is really doing your work a disservice. I don't have an issue with the hand-done nature of the map, but do feel the splitting might not be ideal in the pages version. I also feel like the dotted lines probably aren't needed. It's water. There's not really a path there. I can go from any point on water to another unless there's an obstacle and even then I just skirt around it. Personal opinion on that.
Story so far is okay. Could probably use some tightening of the prose to be a bit more evocative since you're dedicating such a large bit of space to it. I like the bolding of the NPC, but then when I skim the document I don't find any call-out block to tell me more about him. A bold name by itself isn't really super useful other than just remembering what to call him. Points of interest key is fine. It states increased and decreased, but then you wait until the second spread to show what that means. If I were to print it, it means flipping the page over to make use of this when I pull it out two years from now to skim and apply. It would serve well to find a way to put the ebb and flow info somewhere here where you can naturally find it right away.
Encounter list is okay. Some wording choices could be improved. For example: “A buoy surrounded by fog traps the players. Everytime it is encountered, something about it is more eldritch.” The wording implies it is the buoy that somehow traps us rather than being trapped in the fog. I do love how it grows more unsettling if encountered repeatedly though. I'd probably reword this one as “Players are trapped in a fog centered around a buoy. Each time this is rolled, the buoy grows increasingly eldritch.” 4 I assume bat is meant to be boat. No rating issue for typos, just wanted to point it out. 6 has a similar issue with the wording as the fog. A lot of these get really weird if you are crossing between 1 and 8 when they happen. Only 2 make sense.
Initially I was wondering how in the world theme was going to play in this. It was feeling a bit like a generic adventure until the pattern of Lovecraftian elements became pretty clear. The cheerful color kept me from thinking until the world 'eldritch' popped up. You might get better mileage by leaning into the Lovecraft visuals if you decide to work on this further. This could be something as simple as a stylized header bar for the entries.
Another moment of a bold wording, but at least this time it shows exactly where to look because it is bolded elsewhere. What is the whistle? No idea. No call-out block again. The second area at the end is worded like it's actually a spell rather than an object, but the block where it first appears kind of implies it is an item the kids scavenging give to the adventurers. I reread the 'cast it in' and realize it is meant to be cast into the flames rather than cast a spell. Again when I do the 2 year test, I am going to be lost pulling this out of a folder to run on a down night.
The shipwright's home is neat, but it's at this point I am suddenly feeling like I am in a video game rather than a tabletop. I think the limits to access are neat. I'd probably just have the door seal over at high tide rather than worry about complex airlocks and diving. I suspect the video-game vibe is coming from the 'repair and upgrade for treasure' element.
The reef is good. No real comment here. Open ended for me to throw whatever I want in here and a clear value to players who are less combat and more craft focused. The reeds can also make an interesting encounter, but there's a lot of odd wording here. If you work on it more after the jam, I would tighten this up some.
The sunken watchtower is fine. Feels like there is a larger backstory, but the GM's going to need to do the legwork on that. I'd rather this have been more solidly tied to the larger story. The cave... is. It is. A whole story and adventure could probably be built around this idea, but as it is, it's not really gameable. A player reliving a memory isn't probably fun for everyone else at the table to sit through. I have no idea what hugging a memory looks like. I can probably make something up, but again when I am using this as a one-shot, I don't want to be doing this much personal legwork just to make things make sense.
The riptide makes me feel like it swings wildly between dangerous and Monkey Island cutscene. Given the otherwise Lovecraftian vibe I feel like you're going for here, I doubt the latter is what you were aiming for. The lighthouse section is labeled as 'The Reeds' again. The lighthouse keeper immediately makes me think of the game Dredged. Not ideal to have me thinking of video games twice in the same module. Especially since the repair and upgrade thing along with general Lovecraftian elements were also in Dredged.
Lastly, the ebb and flow mechanic is split right down the bottom middle at the very end of things despite being absolutely crucial to the entire design. More importantly, there's no real mechanic to this. It's just 'up is harder than down and figure it out'. With every major element of the module hinged on this, having a patterned method would be nice.
Overall, there's a lot going on here. Clearly you put heart into it and were full of ideas you wanted to get into these pages. I think it came at the expense of substance however. Elements seemed disjointed with the only ties between them being the eldritch natures. There was a lot to explore, but strangely not a lot to do. One of the first places players go is where they get a key object, but if they go wandering to the lighthouse first, the adventure is over right away.
The whole thing is about finding the octopus wizard guy, but almost everything happening is unrelated to him or the quest. I'd have much rather seen things like the sunken tower being where the whistle was hidden. Maybe getting to know the shipwrights son as a way to learn what to do with the whistle is good, but if it's the /only/ way, there are a lot of player groups where they just never find out. The biggest things to improve the overall module would be to tighten up the writing some and to add more cohesion between the overall set of events. Adding more gameable elements to help the GM not do so much leg work would be nice too. Oh, and please change the white on blue thing. Reading this at the printer scale was not possible for my old eyes. Regardless, I hope some of this helps and thanks for entering the jam!