Mapping multiple slightly different underground parking levels

Mall of Tripla has a parking area defined already but it’s missing the level tag for indoor navigation and the round ramps don’t go anywhere.

Should I just add repeat_on=-5--1 and parking:levels:underground=5?

Is there a spec to micro-map parking zones?

What about the “round ramps”? Do the nodes need to be duplicated and assigned layer and level tags?

Should the parking area be duplicated and slightly modified for each level’s shapes? How about ways for common sides and then multipolygon relations for each level?

If I’m doing multipolygon I might as well cut out the ramps and pedestrian entrances.

Here’s an official map:

Are these entrances tagged wrong?