After re-installing the ROM, my battery drain issues seem to be solved and all is mostly well, except.... that the above issue is affecting my phone too, but instead of the external SD card it is complaining about the internal card, which of course is not replaceable. After not minding for the past few days, today the SD card was suddenly reported as damaged but it was still accessible. The disk error checking tool came up clean, no problems fixed or found. Both internal and external cards are formatted as FAT32. I am at a loss, so if this rings a bell to anyone, please let me know. Note that this issue never happened before on Unnamed Gingerbread ROM, so it is unlikely that the SD card is suddenly broken with switching the ROM. Also the fact that this happens on power button pushes indicates that this is not a random problem with accessing the SD card.