You are not alone.

I echo every statement you have made.

Here are the tactics that I have used to adapt to Poser Pro 2010. You are welcome to try them... your mileage may vary.

First, TURN GAMMA CORRECTION OFF and leave it off!

90% of what you are talking about goes away when you do.

The truth of the matter, imho, is that while it does work, and work correctly, it isn't worth all of the problems and limitations that it imposes. For openers, a large number of very useful textures for older items suddenly require all sorts of fiddling and reworking.  This is fine if you know what the heck you are doing in the material room, but for every BB or LaurieA here there are dozens of me... people who know just enough to get by and get in trouble if they become overly ambitious. I have read the threads, and I still have no clue how to adapt older items to GC. Therefore, I think I'm better off leaving it turned off, and doing the adjustments by eye. It has worked well up until now, and I suspect it will serve me for the duration of my association with Poser.

If you need help getting overall light levels to a managable level, try the Tone Mapping feature. Yes, I know it's "fakin' it" but so what? If it works, and gets my workflow on through the pipeline with a result I'm pleased with, what does it matter? I'm not a purist and don't plan to become one.

IDL is the greatest feature I've seen introduced in Poser, especially when you put BB's light sphere with it. That said, it is not a panacea to good lighting. I, for one, find it to be completely unusable in low light situations. Even turning down its native luminance does not give me the effects I'm looking for in very low light situations. In these cases, go back to what has always worked for you and stop worrying. Again, turning GC off will give you the more predicatable results you are accustomed to. Also, when using IDL with the dome, make sure you have at least one real light to cast your shadows. My own view of the dome is it is the greatest fill light I could ask for. For the rest, I set individual lights at about 1/2 the levels that seems right without the dome.

Turning GC off will probably fix the majority your texture problems as well.

Give these suggestions a try and see how they work for you. For me, it's been the difference between a system that works and one that doesn't.