which version of 3cx are you running?
im running 3.1.6288.0 and the transfer action is top left next to the hold button, when i click it, it holds line1 opens line 2 and allows me to dial, when i click transfer again to complete it disconnects the second call and i get an internal server error message.
Maybe you have a later release?
Thanks for the link, i'll have a play with that one.
"There's a dog in the New Zealand section