This LS connection failed should caused by connection of SR3610.
To solve this problem you can try :
1 Check the IP address of Control PC, it should include 2 IP address: 192.168.0.35 and 192.168.0.5 .
You can add IP address : Internet Protocol(TCP/IP) Properties ->Advanced ->Add
2 You can try to upgrade SR 3610 firmware again, maybe the version mismatched.
Find and run C:\Program Files\Spirent Communications\SR3600\SR3600.exe
In pop-up window, select File->upgrade firmware, and select the correct file.