Okay, so the other day I decided to convert my HTC One M8 to a Google Play Edition (I mean the full conversion with OTA updates and everything, not just a GPE ROM). It was nice for a few minutes, but I immediately started to miss Sense, and I'm not a big fan of stock Lollipop like I thought I'd be. So, I used an online tutorial to restore back to Sense, except when I tried to install the custom Sense ROM I was using before the conversion (LeeDroid) via TWRP, I got an error during the install in AROMA that said "set_perm: some changes failed". Then the install failed completely. I tried wiping Data, Cache, and Dalvik Cache again, but that didn't help. Then I tried wiping the System partition, but that didn't help either. I also tried other ROMs like Android Revolution HD and SkyDragon, and those installs both returned similar errors. I can flash CyanogenMod without any problems.
I know that converting to Google Play Edition changes the partition sizes (specifically the System partition), but I followed a tutorial and successfully factory reset my phone via the stock Recovery...so the partitions should be back to normal. I also re-flashed the firmware version I had before (4.16.401.10), so that can't be the issue. But just to experiment, I also flashed an older firmware version (specifically 1.54.401.5) and an older version of TWRP (2.7.1.0) and then installed ViperOneM8 v. 1.6.0 (which is over a year old). For some reason, that worked just fine and I can run KitKat and Sense 6...but why won't Lollipop work?
I'm sorry if this is confusing, but in a nutshell, I can't flash any Lollipop, Sense-based ROMs. I get either a "set_perm: some changes failed" or "some symlinks failed" error during installation in AROMA Installer. I really don't know what those errors even mean, which is part of my confusion. Does anyone have any advice?