I have made an account at www.gmcmap.com & registered my GQ GMC-500+. Now, in the GQ GMC Data Viewer, when I try to set the SSID, WiFi password and www.gmcmap.com User ID & Geiger Counter ID, I get the following error when I click the ""Write to device" button. . The "Webite" field is "www.gmcmap.com", the "URL" field is "log2.asp", and the "Peroid" field is "5". The User ID is the 5-digit one from "www.gmcmap.com" and the Geiger Counter ID is the 11-digit one from "www.gmcmap.com". The (WPA2-PSK) SSID is "SVR", and the SSID password is 22 characters long generated randomly by my commercial grade router composed of alpha-numeric & common punctuation characters. Should all be pretty mundane stuff.
A little experimenting shows that either the GQ GMC Data Viewer or the GQ GMC-500+ doesn't adhere to WPA2/WPA3-PSK in terms of allowed passwords. I found a workaround by creating an additional (insecure) WPA2/WPA3-PSK SSID isolated to it's own VLAN just for the GQ GMC-500+ with a short 9 character alphanumeric password (no punctuation). This is a bug in the GQ GMC Data Viewer or the GQ GMC-500+, hopefully not a limitation of the WiFi chip in the GQ GMC-500+, and so fixable without too much effort.