I have many wxPerl applications running exes and communicating with windows services.

When dealing with GUIs, in addition to our inter communication needs,we worry about blocking issues. To solve these two problems, I find the POE framework very helpful.

You can have a look at these modules in CPAN:
POE::Wheel::Run
POE::Wheel::SocketFactory
POE::Wheel::ReadWrite
POE::Wheel::FollowTail

The last module, FollowTail, could be the easiest to implement for you. The GUI can listen to a file which is being written by some other exe. Everytime you get a new line, a callback is triggered so you get a very good asynchronous behavior.