I've made 2 maps for the ymap version so that you can choose which version you can use. Because ymap doesn't reconize the "hard stand up prop" (that is the car lift
where the cars are on). It's a pity that the lift up is not available under ymap [if you don't mind this then go for the cars up version] The cars down version is a 
bit more realistic. BTW You need also the Map Builder dlc for the ymap version.


Download then Map Editor & Menyoo to YMap Converter 1.0.4 https://www.gta5-mods.com/tools/mapeditor-2-ymap-converter and place the custom_maps folder into;
C:\Program Files\Rockstar Games\Grand Theft Auto V\Mods\update\x64\dlcpacks. Then go to your dlclist; Mods\update\update.rpf\common\data\dlclist.xml
and extract it somewhere. Edit it with notepad add this line;		<Item>dlcpacks:\custom_maps\</Item> save it and put it back. You need OpenIV 
to do this and to work with ymaps. 

Go with OpenIV to the custom_maps folder and search for this line; Mods\update\x64\dlcpacks\custom_maps\dlc.rpf\x64\levels\gta5\_citye\maps\custom_maps.rpf\ 
click on edit [OpenIV] and then right click a blank area where the files are displayed, and choose "Import OpenFormat", when you open a ymap, an import screen 
appears with a blue line [open Formats], with which you can add ymaps to the custom_maps dlc. Choose one of the two ymaps (cars up or cars down) and click OK. 
Close OpenIV and the map will right available at the start of the game!



Greetings GTA5TESTYA