You are going to edit a few files here. Start with getting the zip file attached to this post. In there you will need to copy multidraw_800_480.ui to the ui_pioneer\800_480\ui in your data.zip. Copy multidraw.ui and multicalc.ui to your ui_pioneer\common\ui folder in your data.zip. Copy all of the images to your 800_480 folder.
Once that is done open main.ui in the 800_480/ui directory and add the following line to the top section:
import "ui_pioneer/800_480/ui/MultiDraw_800_480.ui"
add this to the bottom section:
import "ui_pioneer/common/ui/MultiDraw.ui"
Next open the variable_def.ui file in the common/ui folder and add in the following (I did it just above the line with the *****12.16***** in it):
In the same variable_def.ui file add the following at the bottom of the file under the last variable:
Next open the favorite.ui file in the common/ui folder and add in the following to the section at the top below the vManageMode line:
Next open the browsemap.ui file in the common/ui folder and add the following to the bottom of the file:
Once that is done you need to add in a place to launch it in your NavigateMap_800_480.ui file in the 800_480/ui folder with the following action:
onrelease='nextstate d_StMultiRouteDraw'
Since this feature works when in route you want to make sure you use a visible model when the Navigation has route only for your button. The full code that I used was from my Current Speed Sign in the Diaftia mods:
I am pretty sure that is all the steps.