Colorsync and ICC Profile Software, issues creating ICC profiles

Just for clarification, your device is one of these? X-Rite has never seemed to know what to do with that device. It was originally called a ColorMunki. Years ago, I had one of those. In independent lab testing, it was actually a very good spectrophotometer for the price, but the bundled software was wretched. Great at reading spot colors to get Lab/RGB values. But it created lousy monitor profiles, and much worse printer profiles. Sold it.

The ICM files do work. The Mac (or the third party apps) just don't recognize that extension. ICC and ICM profiles are actually the same thing. No idea why MS thought the extension should be ICM, and Apple ICC. All you need to do there is change the extension from .icm to .icc so the Mac will see and use it.

The difference with the same device, but different results on the separate OS platforms is the accompanying software. X-Rite has just never put a lot of work into the software (that's partly why it was much cheaper than, oh, an i1Pro 2). They've promoted the heck out of that hardware under multiple names over the years, but it's always been the neglected child.

Anyway, at least you figured out a hardware/software combo that works.

Good that you found a solution, though it took some hair pulling to do it by trying all kinds of combinations.

It's too bad there is almost no competition for X-Rite anymore. DataColor is the only one left with decent stuff. X-Rite bought out Gretag-MacBeth some years ago. Mostly to get ahold of their far superior hardware. As soon as they had it, all of X-Rite's hardware disappeared, and they put their logo on what was G-M's stuff.

The most annoying part of X-Rite's near monopoly is how quickly they sunset very expensive equipment. All in the name of getting you to purchase more very expensive newer equipment that is generally little different than what you already have. But gosh, the previous hardware just isn't supported any more in the latest software release. So you either spend more money unnecessarily, or you just keep using what you have with the last version of i1Profiler that supported it. And if it's older than that, you keep using your perfectly functional hardware on an older computer.