I do not know which version of CMP you are trying to install but it seems you are not trying to install the latest version of CMP (CMP3), which relies on a conda environment for the installation of all python dependencies (with fixed version) and on Docker container image technology which encapsulates the processing pipelines with all softwares (FSL, FreeSurfer,..) installed. CMP1 and CMP2 are now deprecated and no more maintained and supported.
Please note that I am suspecting that the latest released version (v3.0.0-beta-20200227) might have a bug in launching the docker image from the graphical user interface.
I am working on making a new version release with bug fixes in the very coming days so I would suggest you to wait for it.
Let you know as soon as the new version is released.