Using GHAlex luts Help please

I've just bought the GHalex lut for Daylight.
I've been trying to follow the PDF guidance and I have been getting very poor results but I don't exactly know why.

I use a Panasonic GH5 with a vLog profile. When I put the footage into Resolve I use the Wide Gamut Colour Space and let Resolve expand the flat log profile with its super powers.

And this is where the confusion sets in. If I use the Wide Gamut Colour Space, does this eliminate all the steps the PDF documentation requires to open out the flat log profile before I can use the GHalex lut?

If I follow all the steps then the results are a mess of colours, banding and excessive noise.

However if I use the Wide Gamut Colour Space, ignore the guidance and use the lut, then I get pleasing results.
I still have to dial back the intensity of the lut to about 0.5 or 0.3.

I'm guessing that the Wide Gamut Colour Space eliminates the need for any and all utility luts and lets you go direct to creative luts?
Or am I ccompletely wrong?

What is the color profile that LUT is designed to work with?

Have a look at this page, it may be informative: https://nofilmschool.com/GH5-GH5s-ALEXA-LUT

It would be good to read/view up on how Resolve colormanagement works but here's how you could do it.

The lut is designed for V-Log but it transforms that image to rec.709
RCM does the same for any camera source to whatever your output timeline is set to (probably also rec.709)
Internally it transforms all the data to the timeline space which would be DaVinci Wide Gamut/Intermediate in your case. And then after the node tree it transforms that to the output colorspace.

So to implement that lut in between you need to convert the image back and forth with Colorspace Transforms.
CST: DWG/Intermediate -> V-Log to go back to camera space
LUT: GHAlex which makes the V-Log -> rec.709
CST: Rec.709 2.4 back to DWG/Intermediate
And then RCM does the conversion out from timeline colorspace back to rec.709 again.

You could make a compound clip of all those nodes and tone down the intensity with the key output.