The WiFi tethering problem is solved entering this command in the terminal
su -c "iptables -t nat -A natctrl_nat_POSTROUTING -s 192.168.0.0/16 -o rmnet0 -j MASQUERADE"
It happens in all ROMs based on Kra1o5's sources.
All the problems related to reboots are caused by running out of memory. Flash another kernel than the stock like Synopsis or the repack for CM11 of Chil360's kernel (http://www.modaco.com/topic/371602-kernel-repack-kernel-slimkat-chil360-for-cm11/ for the latest version go to the original post). They will greatly reduce the number of reboots.