Acer A500 Flashing

I had issues with the stock ICS rom until the point where Google Drive apps became virtually useless.  I couldn't edit spreadsheets and Hangouts was crashing crazy.  This post here is to list down resources from my attempted Linux only experience to getting from stock OTA ICS to TegraOwners Lollipop ROM.  A lot of the credit is from the hard-working folks at TO.  There's a huge amount of resources already in that forum so all you need is to search.  (They'll tell you the same thing!)  Since I don't dive in blind with these things, there was a tremendous amount of readings to be done just to get started.

If you're like me and you're in the stock OTA ICS rom, here's the general run down:

1. Root your tablet so the backup factory recovery in /system can be removed.
2. Unlock the bootloader by installing a new one (No more Acer logo boot up screen) that can load custom ROMs.
3. Install a recovery image that can do a lot of magic!
4. Install the custom ROM zip file
5. Install the gapps package zip file

APX Mode

Before you proceed, you will need to know how to boot your tablet in APX mode.  That is done by using a paperclip and pushing the reset pinhole.  Keep it pushed and press the power button for 3 to 4 seconds.  Afterwards, release the power button but keep the reset pushed for another 3 to 4 seconds.  You'll get a blank screen, but the power button should be lit to signify that the tablet is on.

Software Needed

• ICS Root by Blackthund3r (here) - Note that the Linux version is broken and that I attached some Linux-related fixes to that version on the same thread.
• SBKCalc (here) - You need to get your SBK.  I did that by running dmesg on a terminal emulator for my tablet.  Look for the androidboot.serialno section for your Android serial.  Then use the SBK calculator website to calculate it.  This is a critical step because without it, you won't be able to recover the tablet.
• BadSector (here) - This package seems to be referred in the TO forums as Babsector, probably to make it easier to find.  Note that the flash.sh file here isn't the script to use!  The Windows script are to be used.  I attached the Linux scripts in the same thread but they weren't tested.  Since the Windows bat script files are needed...
• Windows :-( - I found Windows 7 to use the scripts on.  I also installed the Acer drivers but it's a pain to find off of Acer's website.  Good luck finding that one as I don't have it with me at the time of writing.  While we're on the subject of Windows, I also dabbled with using AfterOTA which is a nice Windows program that does bootloader unlocking and installing recovery image for you, but it never worked for me.
• Thor's TWRP Recovery Image (here) - Once you've unlocked the Bootloader, this should be installed.
• Skrilax Bootloader (here) - Babsector seems to install Skrilax already but in case you need to update it, grab it from XDA.
• Pick a ROM and the GAPPS (here) - From here on, it's your choice what you want to use.  Make sure to pick the ROM and the accompanying Gapps!

A lot of the things are straightforward if you do your own readings as I did.  Be sure to have your tablet USB cable ready.  Here are some TO threads (here and here) you will want to read.  Remember that with the SBK, it should be very easy to recover your tablet!