Argh, this overpass is being obtuse ...

[Pythias900KMB]

Ahoy there!  As you can see from the attached screenshot, I am trying to create an overpass that leads into a T-interchange.  To the east is a RHW-8S leading out of town while to the west is a RHW-6S that deposits road traffic onto the city streets -- the latter of which I will also require assistance, but one thing at a time.

As I was saying, the overpass that I wish to create is meant to lead into a T-interchange complete with a fly-over ramp to the eastbound RHW-8S (which is to have two lanes because I am directing traffic through the city) and a fly-over ramp curving north to the bypass highway (which I originally planned to make an RHW-8S but have been forced to scale down to an RHW-6S because of my clumsiness and the NAM trying to either read my mind or be obtuse -- not sure which it is yet).  In order to do that, the overpass's elevation needs to be in excess of L2.  I have tried placing the eastbound highway in a trench --only to have demonstrated that the NAM has a sense of humor when I tried that.  SC4 also crashed on me a few times as I was doing that ... not to mention my clumsiness with the mouse.

In any case, what else should I try next?

[Tarkus]

It looks like you may be trying to do too many things in too tight of a space, and if you're trying to use an OnSlope to build an overpass "in excess of L2", there are no OnSlopes from L0-L3 or L0-L4 (there can only be two levels of differentiation with them at most, i.e. L1-L3, L2-L4).  More level ground is going to be needed to pull off such an interchange, too--really bumpy terrain like that will cause real headaches.

Additionally, the RHW-6S is an overhanging network on the shoulder side, so if you try to build another RHW at the same height level right next to it, you'll get some rather ugly things happening.

-Alex