Waveform from HDR analysis tool by Lilium (colors issue)

Hi everyone, i’ve been using this great tool for months, but I don’t understand why the Lilium HDR Analysis tool waveform no longer produces colors anymore for luminance
Someone know what may be causing this issue ?

the waveform is in color at one point to show you what luminance range is. From white/grey for the lower until 100 nits, above this value it’s supposed to display colors blue, green, yellow to red/purple for the highest nits and those colors no longer appear on my waveform graph and don’t know why this happens ! i try to figure it out…