How did qre you saving your "jp2 jpeg 2000"? When I tried saving a photo as "jp2 jpeg 2000" I was not given that message.
I use the RAW which is in PSP in 16 bit/CHannel.
I test now another image and i do the steps.
load a jpg
increase the colordepth to 16 bit
choose save as
and select from the filetype listbox jp2 jpeg2000
In Option i have the settings with loss and compression 75
when press save, the message come that this format support 24 bit and 16 million colors
i test lossless now too, problem is same.I also enable on 1 test the Option only jpeg2000 codestream.Problem was same
I use german psp, i dont know how i can change that to give you precise requester text.
before i buy psp X4 i test the Demo, this was english, but now its german.
I more like all in english, because it is better for support.
EDIT: I have all warnings and automatik Action in prefs in default mode and so it show the warning