I'm afraid I have not played with IPC, also Windows does not implement some functions.
If you run your script from the command line, do you still need to press (Tab+Enter) and then (Ctrl+R)?
Before you try anything complicated you might want to try piping stuff in to and out of the script on the command line to see what you can achieve with dos's < > and |.
eg can you pipe the equivalent of (Tab+Enter) and then (Ctrl+R) into the script somehow?
If it turns out that you need to send (Tab+Enter) and then (Ctrl+R) using Win32::GuiTest then it still might be worth monitoring the output of the script to see what it's done, and when to send the keys. (But Win32::GuiTest can do useful related stuff)
These might be useful:
open() command as filehandle for output
open() command as filehandle for input
After that it gets very complicated, and all I can really offer is a bunch of things to read. And as I said some of this stuff is not implemented under Windows.
perlfunc "Functions for processes and process groups
alarm, exec, fork, getpgrp, getppid, getpriority, kill, pipe, qx//, readpipe, setpgrp, setpriority, sleep, system, times, wait, waitpid"
(These are the sort of functions that Windows might not implement)