Yeah when the HVAC turns on - the lights dim in the whole house slightly - I guess this is not normal? OK what does it mean? I am NOT an electrician, but we have one - who upgraded our house and before he upgraded the house panel to a brand new super big panel - it did the same thing. Back then if our neighbors AC went on our lights would dim as well (before we knew what X10 was ).
So you think the wiring is a bit off for the house. What should I be asking my electrician?
It sounds as if you have a number of things going on.
1) If your neighbors AC affects the lighting in your home you may have a transformer problem - or more correctly, the power company has a transformer problem.
2) The fact that your furnace blower can cause line drops/surges and turn devices on isn't all that surprising. Induction motors can draw a fair amount of current for an extended period of time on startup. You may not be able to filter this. What does surprise me is that you said this worked for a period of time. That implies that something degraded.
3) As for your XPFM's, I'm not altogether clear on the configuration. I can envision the ballast on your fluorescents causing a line spike that would turn on a XPFM on the same circuit. I do not understand why you would not be able to turn the unit off.
On the other hand, if you are having problems with the Incandescent circuit activating the adjacent XPFM, I would be a bit concerned about the wiring. Incandescents do have a surge current on turn-on but nothing like the spike involved with a capacitive/inductive load (fluorescents and motors). I would not expect turning on a florescent circuit to affect anything else.
Start by talking with your electrician. Unfortunately, a new panel does not mean new circuit wiring throughout the house. He will probably have a decent handle on the overall condition of the wiring. Explain what you've been seeing exactly as you've done here - including the loading from your neighbors A/C. He should be able to perform a few quick tests to determine whether the problems are internal or external to your house (or both).