You have to use the software version that matches the version the project is created in.
You can individually install any version, and they will co-exist happily on the PC, even to the extent that if you Open a Project File in RSLogix5000, it will automatically detect the version of the project, and "switch" the software to match it.
When you install any version, you will be asked if you want to install all previous versions that you don't have installed.
My RSLogix5000 has installed the following versions...
10, 11, 12, 13, 15, 16, 17, and 18
Note that version 14 was a "special" version, and wasn't distributed generally, but to one client only.
I'm sure someone will jump in and highlight if there are any issues with installing earlier versions than you already have.