L2 Serial connection fine, UDP does not work with Windows App

[sleeplessTLV]

Hi,
"Serial" connection works as it should, we get point cloud, LIDAR data etc. all fine.
But we need IP connection for longer cable/operation.
We disabled firewall, disabled all AntiVirus.
When we run the test app for windows, Unilidar2...exe, and try to choose UDP connection, nothing happens - no data comes from LIDAR, no command gets executed.
We checked the IP setup is proper - IP of PC is 192.168.1.2, of LIDAR is 192.168.1.62 (ping works just fine).
We checked that when we launch Unilidar App it 'reserves' the port 6201, though it does not display 'listening" when using portqry app.
And nothing ever works.
Any ideas how to further debug this? We think the PC app and the LIDAR firmware may be somewhat incompatible.
Version of Unilidar is V1.0
Version of L2 lidar firmware is
HW 2.2.1.1.
SW 2.5.5.0
NAME YS-L2
DATE 241205