When I output the file as an integer tiff and import it into Photoshop then no problem. When I output the file as a floating point tiff and import it into Photoshop then it is way too light. If I do the same with the v2 profiles I get the same issue. However, with v2 I also have a version of ProPhoto with a gamma of 1.0 (and an sRGB gamma 1.0 profile) and the floating point tiff gives the same reproduction as the integer tiff when I use that one. (I have checked that the RT iccs are copies into the folder for the system colour profiles so it is not a case of Photoshop not having access to the profile).
I get the same results when using the Elle Stone profiles that @ggbuthcer referred me to. If I use the Large with gamma 1.0 then I get the same picture whether using integer or floating tiffs. If I use the gamma 1.8 version then only the integer tiff version gives me the same picture as I exported (and similar to the gamma 1.0 version apart from the expected differences in the shadows).