I cancelled and uninstalled creative cloud and installed a version of LR5 which I had purchased earlier, but it cannot open my lightroom catalog with error message ".. this older version of lightroom cannot open this more recent version catalog". But I know there must be something wrong with this as I had reverted to lr5 even before cancelling CC and it was able to open this catalog.
Any version of Lightroom can open older versions catalog by upgrading them but can not open new version catalogs in old version of Lightroom.
So unfortunately it is not possible to open Lightroom CC catalog in Lightroom 5.
Lightroom 5 will not open the catalog created by Lightroom CC. Catalogs are not backward compatible. You must still have your original Lightroom 5 catalog somewhere. You'll have to get Lightroom to open that catalog, and you will have to start from there.