Problem 2 fixed by adding route to 192.168.5.0/24 on Mikrotik side

@sabrielandoj
If you ping from the pfSense GUI using the Ping tool with the default source (WAN IP) all devices on the 192.168.7.x network should response.
If they don't, but do if you ping from other machines in this network, there must be something wrong in the network settings on one involved device.

If you change the source to LAN it's expected that pings won't work, as long as the devices have no route for 192.168.6.124/25 pointing to pfSense. Responses will be sent to the default gateway.