Sorry for the delay. If you've not made contact with us since, can you run through a factory reset, and if you have an HDMI cable plugged into another device, can you borrow that temporarily?
Hopefully a erasing the data and starting again will fix the crash/reboot issue, and if that doesn't fix the purple hue cast on the screen image, we can check if a different cable helps.
You'll find the little switch you need behind the three USB sockets on the right of your T8. For the rest of the procedure, check
https://droidbox.co.uk/blog/how-to-access-your-droidboxs-recovery-menu/ Ah, just remembered I've put a T8 photo up there already.
Click on the live chat link below if you need help with the procedure.