I seemed to have lost my tall radio antenna tower objects.  Or they might be just a lot smaller.  They are the kind that have all red flashing lights on them.  

Is it possible another library has overridden those models?

I've got 

World-models, Handy Objects, ruscenery, MisterX, OSX, R2, flagsof usa states, FF library, CDB.  Anyone use any of these and notice their obstruction towers have changed?

 

Sorry Boss, all lights are working for me, though I will say they are not as bright as before.  I did upgrade to beta 1 last evening, prior to a short jaunt from KBOS to KJFK, with both of these metro areas laden with lighting and they looked fine.  It was a dark and stormy evening as well so I expected the lights to disappear in the clouds, which they did...another words, all was good on my end.  All of the libraries you mention, I have, and I don't believe they have that sort of control.  Are you using any special plugins, like Reshade or anything that controls the visual effects?

Is there anyway you could load a flight at MN33 (it's a downtown helipad but it's just a street in the sim ha).... and look to the WSW?  There should be really tall towers that go up to approx 2050 ft msl.  In my sim they are still all tiny.  I've removed all my scenery libraries and nothing has changed ARGH.  Maybe downloading that new height adjustment from Laminar screwed with the obstruction elevations?  This is actually really bugging me... it's something you have to fly around when you depart DLH and SUW because they are so tall (or used to be).

Here's what they look like right now in the sim:  dlhantennas by ryan b, on Flickr

And what they should look like (ok its a real pic but they should be a lot bigger in the sim): CgApb6xUYAEGsOP by ryan b, on Flickr

Just out of shear curiosity, you aren't running that XP advanced options Lua script are you?  If so, that could the the core cause of lighting issues.