It's in a subfolder for the GUI project. Do you have any advice on the non standard text in the license? This is a concern I've never had before. Tbh, I'm surprised anyone has read it!
> Please link to <https://raskie.com>, if you intend to redistribute this .exe.
Now that's probably okay so long as it's a nice request ("please"), and not a requirement; AIUI, GPLv3 doesn't (generally) allow you to add conditions (ex. a license file that says "GPLv3 but no commercial users" isn't allowed by the text of GPLv3). But IANAL and I'm sure this is more complex than I think it is. Which brings us to a reasonable useful point: I would suggest never putting anything in a license file other than the exact standard form of the license; adding anything else, at best, makes people have to read it and try to understand what you've done rather than being able to say "oh, it's GPLv3 and I've cached that that's 100% okay for me" and stop thinking about it.
The license file needs to be in the root of the repo.
The first thing many developers who have been bitten by this in the past do is run all the boilerplate files like licenses through diff. Some probably have it hooked to every git clone request.