i made a remote turtle program,
you might need to change some code but it mostly works on its own, if you need to change code it would be them modems side, sorry haven't implemented an auto finding modem code (coming next update).
this is very experimental but works quite well.

what does this program do?
this program allows you to move a turtle using rednet and offers a nice GUI
currently the program can check for blocks around the turtle, move, turn left or right, mine up and down.
also in the gui of this program you will find that if you cant move or mine in that direction the button will be grayed.
this program is secure as to it only broadcasting a pairing code and everything else is sent directly to that id and wont receive any messages from another computer when paired already.

whats comming to the program?
placing and selecting slots
finding rednet modem

pastebins

run in main computer

pastebin get UaKuDxgz startup
put modem on back of computer
turtle

pastebin get 1aytMV2H startup