I see that it shows 8th as a bridge as you say & gives me credit for the change. Not sure how I managed that (not intentional). Clearly it is not.

I did not change SE 8th street. I added the cycle path alongside it. it cross over 8th several times. The only bridge I added was to the cycle path where required as the system recognized the path crosses an intermittent stream just to the west of South Irving Street.

In Oklahoma City, bicycles are generally allowed on sidewalks except in business districts or where signs prohibit it. Cyclists are also subject to the same traffic laws as vehicles, including obeying traffic signals and signs.
Sidewalks and Business Districts:

Oklahoma City law prohibits bicycle riding on sidewalks within business districts.
The city also has the authority to post signs prohibiting bicycle riding on specific sidewalks, and cyclists must obey those signs.

General Rules for Cyclists:

Obey Traffic Laws: Bicycles are considered vehicles and must follow all traffic laws, including yielding the right-of-way and obeying traffic signals.

Safety Equipment: Bicycles must have working brakes and a front and rear light when riding at night.
Reasonable Speed: Cyclists should ride at a reasonable speed.
Lane Restrictions: Cyclists may be restricted to certain lanes.
Sidewalks: Cyclists can use sidewalks outside of business districts.

Additional Information:

The bikewalkokc plan prioritizes sidewalks and bike lanes, especially near schools and libraries.

The City has invested in bike lanes, trails, and sidewalks through various initiatives like MAPS 4 and the Better Streets, Safer City program.
You can find maps of existing and planned bike routes and trails on the City of OKC website.

and I said separated, not segregated. The walkway I mentioned IS in fact a combined pathway for pedestrians & bicyclists.

Not in my city. Sidewalks are an integral part of my cities trail system & bicycle routes. Not all cities ban bicycles on sidewalks. In certain areas of Oklahoma City, bicycles are prohibited (entertainment district, etc). otherwise bicyclists are encouraged to & routinely ride on sidewalks.