I took to the CPAP surprisingly well. I didn't like that I needed it, and it was weird the first couple of nights, but I adapted easily and have used it all but maybe two nights in seven years. The sleep lab had me correctly titrated, and the machine has done the trick. When I nap, which is like three times a year, and forego the CPAP thinking I'll not need it for the 20-30 minutes, I'm always proved wrong....I fall asleep but instantly awaken snoring. I have to use the machine....period! I never snore while using the machine. The OSCAR software over at apneaboard.com does a fine job of revealing each night's sleep record, and mine are always excellent with a running average AHI of 0.6.
Your low oxygen suggests to me that your machine is not set up for you properly. It isn't 'splinting' your airway like it should, so you end up hypoxic. This is not what CPAP is for, to be endured and to offer no remedy. I urge you to register at apneaboard.com, download OSCAR, and if you have an SD card in your machine (you should), remove it and let OSCAR analyse you and your machine's interface. Also, you might wish to place your results before the crowd there and let them offer you some advice or feedback. We do a pretty good job, especially if what you have isn't working well, but it is still the right equipment.