Hello all!

I am a longtime BMW enthusiast but I have recently acquired my first X3, a 2007 Highland Green 3.0Si model with manual shift and tan premium interior. I am in love with the car and have been greatly surprised by what it's capable of. I feel like E83 X3's are very underrated.

Being an older used car there are a few glitches I have been trying to take care of. I am also looking to figure out the preventatives I should be considering. So far I have given her new plugs, coils, tires, oil change/filter, and a transfer case fluid change. I recently had the oil pan drain timeserted as well as the threads were blown out there and allowing a leak. I have already purchased springs and shocks for the rear as the rear springs are broken (characteristic suspension sag) and the fronts are already upgraded with Bilstein B6's so I want the rear to match as well.

Some of the outstanding things I was hoping to get help/advice on:

• I have had quite a few issues with the power windows. granted, i've been owning BMW's for many years now so this is nothing new. My D/S Rear regulator failed in the first week with the car, and I diagnosed (based on research) that the drive dog had failed. Fairly easy to replace and this gave me my window back for about two more weeks, then it failed again. This time the metal swaged bead on the cable lift mechanism failed, allowing the drive dog to freely slide on the cable (and not lifting the window). I have rebuild the regulator with a repair kit, but I feel like something else is causing the problem here. I have already greased the window gasketing with Shin-Etsu but it does not seemed to have helped. I was going to try a tube of Gummi-Pflege next, but should I be considering anything else?
• My pano roof floating headliner is sagging which I know is a common issue on these cars. I recently made a scrapyard run to acquire two floating headliner sections that I can re-upholster with the correct Tan liner material and then install. Are there any good sources out there for getting the correct pattern and weave of material?
• I have had some intermittent trouble putting gas in the car - it is clicking off the pump. Normally this would only be a minor hassle but because I live in NJ it's an even bigger issue as I can't pump the car myself. However it is doing it intermittently - I can go several fillups without any issue, then have 2 or 3 in a row where it will not accept more than a few dollars of gas at a time. As a note I do not top off my cars and usually only put in $20 or $40 of gas at a time to avoid that issue. I have already acquired a charcoal box and DTML pump (same scrapyard car) but I'm not sure if I should be looking at anything else?
• Second and occasionally third gears are pretty notchy to get into. My '99 528i has a very similar ZF 5sp gearbox which exhibits a similar characteristic which seems to be a quirk of ZF gearboxes, but to a less noticeable extent. Has anyone else had a similar experience? Should I be changing my gearbox fluid? Any recommended brands? (I use RP synchromesh in my 528 but open to other choices).
• My passenger cupholder is broken, another common issue evidently. Any decent aftermarket replacements available, or repair kits? Or am I stuck getting a new one from BMW?

Thank you all!