Thanks bcimini for your very fast reply. Indeed I did not know about that in version 3 and the CLAHE, except the discontinuation of "RunImageJ" - I guess it anyways did not work smoothly.
My "computer guy" wisely installed CP3rc1 on my cluster node, so I will try that. In regards of the Fiji-color deconvolution, I decided anyways to run that prior CP, so I use the fiji-separated channels as input for CP, which also will work well. I understand that CP is mostly not used for color images, so that kind of color deconvolution (in contrast to unmixing) maybe not have much interest.
Thanks gain for the fast answer.