Maybe to answer the second question first. I have a free programme - Treesize- where you can see how big various folders are see:
How did CMAK get on to your PC - I thought it was for servers rather than PC. If I were you I would run create a restore point, then uninstall it if it appears in the "Programmes and Features" part of Control panel. If something goes wrong you could restore to square 1.
How big is your system restore? Mine is set to 15% of disc space.