Joe,

To (attempt) clarify:
Lets say for arguments sake you have a Xantech 791-44. This is an amplified connecting block with 10 emiiter ports. Other features aside, we'll use it as a one input, ten output block. Essentially this is the same as the IRF-6 except the IRF-6's input is RF only. We use the IRF-6 only as an RF to IR converter with one output.

First, disconnect power from both IRF-6 and 791-44.
Disconnect all emitters from the IRF-6 and connect them to the outputs of the connecting block. Use one of the IRF-6 ports to connect to the input of the 791-44. You'll need an 1/8" jack to bare wire cable to connect to the signal and ground on the 791-44's terminal input strip. The other 5 ports of the IRF-6 are not used. The third party keypad's IR output (similar to the IRF-6's output) is also connected to the 791-44's input; parellel with the IRF-6. You will have both 'IR outputs' going to the same input on the block. Connect power to the IRF-6 and the 791-44. and off you go.

This is for a single zone IR system. If you need to route IR, you will need a multi-zone connecting block.

Hope this helps.

Rob