Make sure all patches and addons are already installed.

Unzip the rts.dll file and follow directions.

Open conf.ini. file in main il2 folder and use the example here to make
the correct changes for the game. There is an example of what the file
looks like and in the wordpad has the 5 things to change.

Simple enough.

Note: if game wont launch with rts no cd file, once installed use cd for 
first game then try again after that with out it. Sometimes just needs
the cd for first launching.