Marcel,
Try the following with the + added:
SEND "+CIS" WAIT "D:" SEND "+Your_User_ID/GO:PPPCONNECT"
I also think Chris's script had you on the right track. It seems like your
ppp0.config file needs some adjusting. Here is mine….
serial.device 0 38400 0.0.0.0 7WIRE CD DIALSCRIPT=AmiTCP:bin/dialscript.CIS
Try using 384000 instead of 192000.
Good Luck!
Tom