Wow! Thanks for your help again. A lot of info. I'll respond in bullet points to keep this somewhat organized for me. If M works, that would be perfect!

- All my data are from the Canyon website - the "geometry" charts of the individual bikes. There, I noticed that CF 7 & 8 have different numbers. Thanks for clearing up that they're indeed the same. Although I'm not sure which of the numbers I would need to go with if I do take another look at the CFs.
- The SLX/CFR L size geometry specifies Saddle Height range of 775 - 895. Mine is 772. My bike fitter still said to go for size 'L' because my front end (stack & reach) gives better range in all directions on the L frame. At first I thought he didn't check the saddle height range, but he replied that that range actually extends lower if you don't use the rear bottle.
- I'm in Taiwan. Hopefully I can swap that crank. Thanks for outlining the swapping process should I have to do this post purchase!
- My saddle angle is -5.5 degrees and the ISM PN1.0 worked best. I used that on my previous TT bike (which I no longer have) and currently use it on my road bike w tri bars where I also have it set up with a - 5 or 6 degree angle.
- You said "If it's an SLX (or CFR, same in terms of fit)... Medium, high spacer, mid extension, short stem... everything we stated before (at 656-480). That's a fine fit." If I can just go forward with the M that's in my shopping basket that would be great. But I'm a bit confused because the geometry chart suggests to me that at my 460 reach I'm already at the end of the range (408-463) and wouldn't be able to move forward. Are the 656-480 numbers that you use my potential future position? Isn't the 480 reach beyond the range of the M? And I should go for the mid extension and short stem? I thought I need to push things as far forward as possible to get to 460. Please help me understand where I'm making the mistake. Really can't thank you enough, Ian.
- Attaching pictures and measurements from the fit.

All my best!!