Don't try to install OTA update. It may brick your device. OTA update requires stock recovery. Disable Motorola Update Services to stop update notifications.
If TWRP didn't even tried to flash it, then this might be of help. I tried modifying RR ROM to remove magisk and learned this-How can I flash this without ROOT and BUSYBOX?
I have located the updater script by unzipping the zip file, and inside that I can see the sections for ROOT and BUSYBOX. I tried to remove those sections and zip the folder again and flash but it gave me error in TWRP that its an unsupported zip.
Go to settings > application manger> choose play store >clear data and try.
/* * Your warranty is now void. * * I am not responsible for bricked devices, dead SD cards, * thermonuclear war, or you getting fired because the alarm app failed. Please * do some research if you have any concerns about features included in this ROM * before flashing it! YOU are choosing to make these modifications, and if * you point the finger at me for messing up your device, I will laugh at you. */
Install the apk first then Just flash the latest zip in recovery which must contain sdk23 in the name as it is for marshmallow. Wipe dalvik afterwards.