Whilst playing Road to Independence episode four: United States the following happens in both vanilla, TAR 2.0 and Darthmod.

After the first turn, all countries display the same technology trading screen in diplomacy (this happens even if one presses end turn without doing anything else). I am unable to offer any technologies, and all countries display the same demand technologies namely: reformed naval administration; carronades; diamond formation; fire and advance; new model bayonet drill; copper bottoms; lime juice and sauerkraut; national debt and wealth of nations.
Have no idea what causes this.
Further to the above Mysore just offered an alliance and techs: fire and advance, copper bottoms, and lime juice and sauerkraut. This suggests that this glitch affects all countries giving them all the same advanced tech.
If this is so than the Road to Independence campaign becomes unplayable in that all countries are given the same advanced tech except the usa. This problem is avoided in TAR Campaign games, but not in episode 4 (either version) I would suggest that anyone wishing to play the 1783 campaign use TAR 1783 campaign game.

There are other known tech bugs see:
http://forums.totalwar.com/showthrea...nsfer-function
http://www.twcenter.net/forums/showt...ght=technology
http://www.twcenter.net/forums/showthread.php?t=303065
http://www.twcenter.net/forums/showt...chnology+trade