If you use a line-level auxiliary output from your rig, you must arrange for an RX level control. This is the only software which will also transmit and receive GL-Hell, and it also transmits very good Morse. I have a special upgrade that includes beacon mode and text file transmission, but it is undocumented. Send me a note if you are interested. Here's an example from the LA0BX software.
Double width is much slower, but more readable under poor conditions, or when the typist is slow.
The Windows receive software displays multiple lines of text. Unfortunately, neither of them have a useful type-ahead buffer or backspace, so you need to type fast and accurately. The software available here includes Windows Help and a READ.ME, both of which you should read before attempting to run the program. No special filters or other equipment is required. This software for Win95 PC and sound card is aimed at extreme QRP and LF experiments.