Some, if not all paintjobs are outdated. Unless during your hunt for a sweet paintjob for your ride is filtered by latest versions, chances are you had installed an outdated one. Check through your downloads and make sure they're at least of September 2018 versions as the installation paths/rpf folders had changed during those patches.

Replacement mods involves overwriting your game files unlike addon mods. I suggest you look through your mods' installation readme text files and check which game file/folder needs to be copied over.

For an example for alex189 & saldin93's Holly Summer & Sylvia Christel No More Heroes [Add-On Ped | Replace] v1.1 mod, the replacement method requires you to have "x64v.rpf" in your mods folder. Other replacement mods may require different files & folders so you really have to look through all of your replacement mods' installation readme again.

@MIC97 Go to mods > update > update.rpf > x64 > levels > gta5. You should see this "popgroups.ymt". If you wan't add-on cars or peds to spawn automatically, you will have to edit this file. Extract the file to anywhere you want and edit it.

Use CTRL + F to search for the term "vehGroups" without the quotes. You will see the group "VEH_POOR".

For an example if you want to add an add-on car, do this;

<Item><Name>YOUR VEHICLE CODE NAME</Name><Variations type="NULL"/></Item>

Put it in line in one of the groups in the file. Here are some of the groups;

• VEH_POOR
• VEH_MID
• VEH_RICH
• VEH_HAULAGE
• VEH_UTILITY
• VEH_FREEWAY
• VEH_LARGE_CITY
• VEH_COUNTRYSIDE_OFFROAD
• VEH_COUNTRYSIDE_ONROAD
• VEH_BIKES

Just know that each group serves different area of the map. I'm sure you wouldn't want a super car to spawn on the countryside off-road.

The same applies to add-on peds.

@Psywriter MP Female mods are meant for SP mode. The reason why they are called "MP" is simply because they are exclusive peds for the GTA Online which, you won't usually see in SP. Thus, the installation methods are very different from the normal SP ped installation. You can easily use a trainer which supports ped spawner to either spawn or replace your main character with it.

@Lazykore If you updated or did a full replace of your Addonped mod (since it is a new version from your previous), check your AddonPeds editor. Make sure the values and names stays unchanged and counter-check those names in your peds.rpf folder. Also, make sure in your dlclist for the addonpeds have two backslashes; \addonpeds\