If you were closer you are welcome to mine, it's supposed to work.

Trans x may help, but it just swells seals, won't help with worn clutches. It does a nice job cleaning stuff out though.

You can run it for a while let everything get hot, shift into each detent and let the fluid circulate. You can also try shudder stop, or putting in some trick shift from B&M. It is aggressive ford type fluid and helps the clutches grip.

Automatic transmissions are not scary, in fact easier to build than manuals. Worst part is cleaning them. Heat really does a job on them, makes the seals brittle, makes the clutches wear out, or even lock up.

Looks like there is one band, and i'm guessing 3 clutches. The band is in the rear so i'd guess it is for low and reverse, you might try adjusting that to gain some life. And I'm guessing here, I never looked at a bw35 manual, but they are all pretty much the same. With the center support it looks like an FMX which was a copy of B&W's aluminum version.

Pressure is a bit higher in reverse, but could also mean it's the forward clutch that is giving you problems. FC is applied in all forward gears. Reverse is usually the band (low & reverse) and the direct clutch. Again, going from generalizations, but hope that helps what may be going on in there.