Can we install coreldraw x5 as well as x6 on a system & use them one by one?
Yes you can use both versions simultaneously. The only point to remember here is lower version should be installed first.
You can install two versions and they will largely work independently because each has its own default path, data and registry keys. In this respect CorelDraw is better than many other programs which try to throw both versions in one place.
You will be able to use both versions for most things, but there are some things to remember ... those I can think of offhand ...
Hey, folks. Coming back to this question, I'm reading here that if I have one version installed and try to install an earlier version, I will have issues with some features, like thumbnails and file associations. Can I uninstall the later version, then install various versions of DRAW in order from earliest to latest and expect everything to work okay?
Yes, that should work