G-PSK31 und Twpsk

Hallo OMs!

I'm Peter, DL3VPZ from Dresden. Today I've installed the gpsk31.
I have no problems to receive psk31-station and I also can say "F11" for
sending my own text, but than I have a problem: There's no other way to
come back to the receive-modus than to close the program!!!  :-(

Do you have a hint, what this can be? An other dig-mode-programm (qsstv)
is doing a good job switching transmit/receive...

The button "Abort transmit" isn't highlighted, so I can't press ist!

Thanks for helping me!

73 de Peter.