Exported OpenDRIVE contains too many Maneuver roads

Hi. I'm trying to build a scene of a port, so the roads are very close, like this

And I need to link every lane, like this

But the junctions are too close. When I import to Appollo or OpenDRIVE file, the junctions are exported as one junction. It generates all possible connections, like this

It will contains millions roads if I draw all the maneuver roads, and Roadrunner will be crashed.

I just want generate those roads I link with maneuver tool. How should I do?

Or I tried to make these roads as one road with many lanes, like this

But the Maneuver roads can only be linked to the long road's ends. It's too long for the curve.

Any suggestion please. Many thanks!