There are a couple of reasons that it might be harder than usual to successfully beat the game.
1. You are maybe playing an outdated version of the game. That means a few crucial bug fixes + a balance pass on the latest patch to make some key elements easier to obtain. Here's the latest patch -
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2. If you are relying on the Guide in the OP, it is outdated. It's for 0.99 (I think) and some things have changed since then, making the Guide lead you in possibly wrong directions. Here is the latest one -
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If you still have trouble finishing it with the latest Guide (and you do have the updated version), I've attached a 100% save file if anyone wants it. But I'd still urge people to try and give it a go, as it's far more enticing than a plain CG Gallery.