Help downgrading from TWRP 2.8.5 to 2.8.0.1

Mac Os X - adb tool and fastboot installed.
Xperia S lt26i

I had the 4.1.x Android version, and I wish to install the Lollipop 5.1.1 version.
For doing that I need to install a ROM.
To install a ROM It may be usefull to have a recovery tool.
I'm using TWRP 2.8.5.0 as a recovery tool.

Problem:
Each time I try to install the ROM uCyan-12.1-b05.zip or simpleAOSP.zip, I get the same error:
It hangs on

Quote:

"detected filesystem ext4 for /dev/block/mmcb1k0p12"

, and, after a while, I get:

Quote:

" ... Operation not supported on transport endpoint set_metadata_recursive: some changes failed ..."

After some research I found out that, this error may be related with this warning message that TWRP provides:
" Kernel does not have support for reading SELinux contexts"

After some other research, I found out that, in order to avoid the error, I should use a OLDER version of TWRP, for example: 2.8.0.1.

If this is true, and if this is my only way around, I don't know how to downgrade to the older version.

I tried:

Code:

---

"adb reboot bootloader"

---

But the device simply restarts, and get's loaded into TWRP again.
No blue light, nothing.
Without being able to enter on the bootloader mode, I don't know how can I re-install the older version of TWRP necessary to install Lollipop 5.1.1. as desired.

Can anyone please help me out.
I'm stuck.

:(