The debut of the Windows 8 Release Preview yesterday was a key milestone in Microsoft’s march to release its new operating system later this year.

I’ve been using different versions of Windows 8 off and on since last September, when Microsoft released the first preview for developers, and I’ve received guided tours in the past from the people in charge of designing the user interface.

In short, while I’m certainly not the biggest Windows expert on the planet, I’m far more familiar with Windows 8 than the average computer user will be when it’s released.

And yet I’m struggling to get comfortable with the idea of using Windows 8 to power my primary desktop computer.

I’ve been using the Release Candidate since it came out yesterday. The difference this time is that I’m testing Windows 8 on a traditional keyboard and mouse, not on a touch-screen tablet loaned from Microsoft, which was my primary (though not exclusive) way of testing Windows 8 in the past.

Bottom line, I’ve spent the past day feeling lost, and a little grumpy. (Grumpier than usual, at least.)

The Metro apps are beautiful — and there’s a lot of slick new ones to check out in the Windows Store, to Microsoft’s credit. But my biggest struggle, as a user, is that the full-screen approach to the apps is disorienting. There’s no immediate context beyond the application I’m using. It feels like driving down a highway without seeing the shoulder of the road in case I need to pull off.

How do I get out of this app again? Oh, right, I have to point my cursor at the corner. Wait, not that corner, the other one.

Yes, I can hit the Windows key to quickly go back to the new tile-based Start screen. And yes, I can click one of those tiles to go to the traditional Windows desktop, minus the familiar Start button. But then I have to switch back to the Start screen to launch one of those cool new apps. Then I’m back on that shoulder-less road. And then where do I go again?

Speaking purely for myself, it’s not instantly intuitive. It feels like a forced mashup of a desktop operating system and a tablet interface. (Maybe Apple’s Tim Cook is right about toasters and refrigerators?) Microsoft will contend otherwise, but that’s how it feels to me as a user.

No doubt it will feel more comfortable over time. But I wonder how much patience other users will have with this when the finished version is released.

Microsoft likes to use the words “fast and fluid” to describe Windows 8, but two other words keep popping to my mind: “New Coke.”

Update, Saturday: GeekWire reader Mike Whalen was inspired to do a dramatic reading of this post. Enjoy. (And thanks, Mike!)

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