I am now convinced that I need an XTB-IIR. Yesterday I did an install inside my ceiling fan in my office area of an XPDF for the light and an XPDI3-IW for the fan. I also installed an XPT switch (3 on/off w/dim) to control it. Today I was doing some testing with my XTBM plugged in to an outlet in the room that is on the same circuit as the fan. When I use the XPT wall switch/transmitter I get a level of 5.03. From the CM15A I am getting a signal level of 0.52. A few times when sending from the CM15A I was getting erroneous results. Sometimes the XTBM might say E03 OFF, sometimes It would just show E03 and sometimes nothing at all or <NOISE>. I think a boosted signal would solve a lot of these problems. I currently have an XPCR connected which has been doing okay except for a few things like this. I'll be ordering my XTB-IIR soon.
BTW, I put the XPDI3-IW inductive dimmer on my ceiling fan to test what people here said about dimmers like these causing hum from the fan. Surprisingly there is absolutely no hum. In our guest bedroom, the previous owner wired in a dimmer slide switch to the fan in there, and I hear significant hum from that one. I will be putting the same setup in that room as I did in my office. Curious to see if the fan hums...