I've been out of the X10 game for many years and am having some issues trying to figure out what route I should go to control the lights in my home theater. It's pretty basic...I am using Kodi and there is a plugin that will allow control of X10 devices. All I want it the lights to dim when a movie is played and come back up when the movie is either paused or stopped. ....
It was my Home Theater that got me into X10. I also wanted to be able to dim my lights from my seat.... and my harmony-logitech remote (630?) had X10 codes. I use the remote to send an IR to an X10 (IR543) IR receiver that sends a X10 command on the power line. Then I added a X10 (CM15A) AHP loaded with some macros I created. The IR543 is located directly under the screen along with an X10 PowerMid sender that relays the other IR signals back to the AV equipment.
I used 3 (X10) wall switches for overhead lights, 2 (old style) lamp modules for cabinet lights, and 2 appliance modules (1 for the sub-woofer, and 1 for a clock).
I decided I preferred not to dim. The macro turns the ceiling lights off. Front lights first, then middle lights, then rear. Then the macro turns the clock on... as well as the sub-woofer. The harmony-logitech remote also turns on the DVD (now BlueRay), Receiver, and projector.
When the movie ends... I found it worked better to only turn on the indirect cabinet lights. The over-head lights are blinding!
I've upgraded the theater regularly. Although I have a big DVD/BR collection... streaming is the way to go now-a-days (I use a Roku device). It is now HD, HDMI... and the next upgrade will include a new 4K projector.