Draken 5.0 is installed outside of the Prepar3D program folder. All versions in the 5.x series will be installed in separate folders and should not conflict. Patches/hotfixes that are issued between the release versions may overwrite files in the current installation.
Draken 4.1 is installed in its own aircraft folder and in sub-folders within the main FSX gauges and sounds folders. The effects files are specific to each version and will not conflict with previous versions. The included scenery files will be updated from earlier installations and are fully backward compatible.