Product review (1 stars): A fragile configuration process backed up by unskilled and indifferent support people
It takes a lot for me to do a bad review, but this one deserves it. Their website support section says it all:

"Sensor registration is based on a sequence of timings that must occur correctly."

You'll need the timing of Buddy Rich to pull this one off I am afraid. I am a network engineer with almost 20 years experience with IP networks. Couldn't pull it off.

Day 1: I connected the La Crosse gateway to the internet, using an open IP address that has free access to the internet, assigned via DCHP from our router. I went through the online activation at my PC workstation -- the gateway registered correctly and showed a solid red LED light. Meaning, it was registered to the La Crosse Alerts account I had just set up and "could see" their server. However when it came time to link the sensor to the gateway (the sensor takes the actual temp/humidity readings and feeds the readings to the gateway, which passes them to the LaCrosse Alerts service --), there is an issue. I followed the instructions online (press sensor button then gateway button) and when the two should've linked, they did not. Therefore, the full activation COULD NOT occur. You can't complete the last step unless a) the gateway links to their service, and b) the sensor links to the gateway.

Day 2: Called in and they advised a factory reset of the gateway. Hold in the grey button while power cycling the gateway, waiting, etc and so on. This should put the gateway into a state to allow the sensor to link to it -- four red flashes, pause, four red flashes, etc. and so on. It does not. We get nothing but a continual blink of the red LED light. Technician says that means the gateway is not registered. He claims "something is blocking" the gateway from accessing the internet. I know this NOT to be the case. Just to humor the fellow, I connect my laptop to the same ethernet cable, assign it the same IP configuration, and viola I have internet access. Then he starts talking about a setup software tool to assign the gateway a static IP (leading me to believe their DHCP routine is buggy).

So then I get the software tool, assign the gateway various setting using both DHCP and static IP assignments. No luck. It can't connect to their service. Day one, it connected fine, though the sensor was an issue. After a factory reset the thing is just a hunk of worthless plastic. And worse there is no one there I could get on the phone that understood basic IP networking concepts.

One mention-worth quirk is that the ONLY time I could ever get the gateway unit to do the "four blinks", showing its ready to link the sensor, was by using their software tool to tell it to use a proxy server. We do not use a proxy server, and a proxy server certainly is not needed for internet access. So then what happened? The sensor still failed to link up. Go figure.

My best guess is when the initial activation failed, there is something in the account we have on their server that is preventing us from "starting over". Guess we'll never know. It's going back to Amazon. Oh well.