Here's a fully completed save (all CG, all achievements). I made it for version 1.03. The current version in the OP is 1.01, but you can get the 1.03 patch at NekoNyan's site
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. In the pre-patch version one of the (non-H) CG won't unlock on page 9 of the gallery.
The file in this zip archive (system.dat) goes in the folder called SaveData which is in the folder with the game executable. As for side effects, this will reset all your settings (message speed, volume) to default.