A bit belated but I gave this a try based on a recommendation I got in the GOTM20 spoiler thread 1....where I begged for guidance after falling way way way behind in tech.
I did 21 trades (can't decide if the 21st was worth it though)
1) 32g to India for Contact with Babs
2) 202g to Zulu for Lit
3) 475g + WM + Lit to English for TM + Map Making
4) WM + Lit to Rome for WM + Contact with Greeks + Philosophy
5) Horse Riding + Myst + IW to Greeks for WM + 50g
6) WM to India for WM + Poly + 3g
7) TM to Egypt for WM
8) WM to India for 20g
9) WM to Japan for WM + 1g
10) WM + Contact with Greeks to Zulu for Math + WM + 158g
11) WM to Rome for WM + CoL
12) Peace + WM to England for Peace + WM + 123g
13) Peace + TM to Babs for Peace + WM
14) WM to England for 59g
15) TM to Russia for WM + 21g
16) Peace + WM to Persia for WM + 39g
17) WM to England for 34g
18) Peace to Zulu for Peace + 44g
19) RoPassage to England for RoPassage + 75g (they're so far away....not getting there in 20 turns)
20) WM to India for WM + 9g
and the questionable last trade:
21) Math to England for 204g
At the end I had:
906g + 26gpt
All Maps
RoP with England
Tech situation:
parity with England (was it worth 204 to give them Math? not sure)
+5 techs over Japan
+4 techs over India
+2 techs over Rome
+6 techs over Egypt
+2 techs over Persia
+3 techs over Zulu
+5 techs over Rome
+3 techs over Babs
+6 techs over Greeks
Greeks have no contact with: Japan, India, Egypt, Persia, Russia
Edit: noone had any gold except England who had 53g left.
I think I could have improved this by trading Peace to get contact with the Babs and maybe Phil. Might have saved me some gold (probably not much), kept the Zulu and the Romans from contact with the Greeks if I did it right, and kept Lit from the Romans. Not a huge difference, but every little bit helps I suppose.
Also screwed up #16. Didn't have to renegotiate peace to get deal from Persians.