Make sure to create a NAT entry to NOT NAT any traffic from your "protected Network" to the remote Network. The order of the NAT entries is important also (that was my problem)

I got mine working, my issue ended up being a NAT configuration issue on the ASA side. Once I resolved the issue, the tunnel came up and stayed up

I'm having the same issue with getting a Fortinet to connect to ASA.   If I protect 1 network then the VPN connects, but if I have multiple, it fails