If I tune into a signal, if I then try to reply the green rx line jumps across to the red line, so that I am transmitting on a different freq to the station I heard. It should surely work the other way round...the red line ought to jump across to the green line so that a qso is possible...what have I missed...can't find it in the manual. R=T does the same thing when pressed...the green line jumps to the red line and not the other way round!

There are different "switches" for the TX and RX freq.: Some of them (T and R) are only for displaying, e.g. on the frequency display.
But more important is to "link" both frequency's to change it at the same time.
You find a "L" switch on the VFO knob and also on the Bandscope. Press this icon - and you will link both frequencies together as one.

With "T" you can change only the the transmitting side (TX) and with "R" only receiving (RX) (only interesting for "split-mode"). The normal mode should be "L".
That's all.

73 and good DX from Jörg :-)
JO31ok
Bochum / Germany