This worked. Thank you. Updated to 3.4.0, it still wouldn't install the update. A couple of days later, 3.4.0-1 came. I installed that, and after installation, instead of downloading the 740 mb update, it downloaded the 1.9 Gb update, and after that, it installed properly. I am now on latest global stable and got official TWRP with root.Your TWRP is too old. There's version 3.4.0 on the official TWRP site.
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Thanx a lot for your help