Alright here goes. Hope it's clear. Learned this on another forum. 1st step is to get a solid end to one of the versions and create a separate file such as "Man of the House" and save that good game to it. If you want the mod then download it and install the new mapping file. Next step is to download the next version but keep the same name. The new download does not have any save files so you would have to start from the beginning but you should still have the file you created that has the save files and the mod if you installed it. Next go to the new version extracted file and copy all files except the mapping. Paste those files to the new game file you created in 1st step. You now have a game file with 1 the new game file 2 the proper mapping mod and your saves. Then just play the new version from the game file you created and not the extracted version download.
Have been doing this since about version 6.5 or so maybe even 6.2. works like a champ every time. Of course you also get any bugs but only those in the new version.
Edit: One clarification. This only works when you have a completed version just prior to the new version so you will still have bring the latest version up to date by asking for help or save files and other means. You should not get any bugs from previous versions because
@Faerin is great at cleaning up bugs.
IMPORTANT: Make sure you have a solid end of version game file before you do this or it may not work.
Let me know if any questions or if not clear maybe someone else can write it out better than I did. thx.