Personally i follow the procedure as mentioned on XDA thread ..
fastboot boot twrp_renoir.img ( phone enter at TWRP )
Advanced >> Flash current TWRP
Then Reboot / System ( phone turned on )
Then from powermenu .. / Reboot / Recovery ( phone enter at TWRP )
Touch is working without issue for me , i can continue to flash rom .. i reboot to system once again and then again with powermenu reboot to TWRP just to check touch again and still working ..
I continue to flash 21.7.14 by dirty flashing over 21.7.14 ( fastboot rom ) ..
Flash seems that goes well , after flashing i choose the wipe dalvik button , wiping dalvik and then Reboot to System BUT then a message that No OS installed you want to reboot anyway .. i swipe left to reboot anyway , after 4-5 minutes phone turned on without problems ..
Again with powermenu , reboot to TWRP , touch works like a charm for me , then i try to reboot to system and i saw that ( below has two buttons slot A and slot B that there isn't there before ) , anyway i choose System and phone turned on and still working fine , i will wait the next update to test further ..
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