follow the instructions carefully:

1. copy mpheist and mplowrider updates to your mods folder.

2. put all heist ymap files by drag and drop to replace at.
\mods\update\x64\dlcpacks\mpheist\dlc.rpf\x64\levels\gta5\_hills\country_06\country_06_metadata.rpf

3. put also all low_rider ymap files by drag and drop to replace at.
\mods\update\x64\dlcpacks\mplowrider\dlc.rpf\x64\levels\gta5\_hills\country_06\country_06_metadata.rpf

4.Now drag and drop starbuckscoffeestore dlc folder to ...
D:\Game Files\Grand Theft VI\mods\update\x64\dlcpacks

5. add the new dlc entry 

<Item>dlcpacks:/starbuckscoffeestore/</Item>

to dlclist.xml at ...
\mods\update\update.rpf\common\data

6. Enjoy the new dlc and don't forget to rate or comment.