Wi-Fi connection failure

[Raspador]

Need help here, probably a lot of it

Bought my 6700 a month ago and it's been working great otherwise, got round to trying the wi-fi functionality and spent 21 hours this weekend playing and reading posts to no avail.

This is the Sprint version, had the 6.0 kitchen on it when I got it, flashed back to 5 for provisioning, then flashed the 6.1 kitchen. EVDO and Bluetooth work fine. Problem is it doesn't connect to my d-link DI-524 router at all, and only sporadically to other open points. I removed the wifirouter app that was in ROM by flashing a new 6.1 kitchen today, made no difference.

Router was originally running WPA-PSK but I ran it open unencrypted to try this. It's running mixed mode and I tried both long and short preamble. Currently it serves via wireless my desktop and my laptop, and another desktop's hard wired to it.

The HTC will try to connect, say "connecting" then give up and declare my network "unavailable". Once in a great while it will connect to a neighbor's wi-fi and work slowly-it was on all day and worked with a neighbor's linksys (I think) router for about a quarter hour, then wouldn't connect again. It connected once today to a nearby college which has a free open wi-fi. I took it over there this afternoon to see what a stronger signal would do and it wouldn't connect at all.

It seems to discover networks perfectly well.
Where is there some documentation on the "tap an adapter to modify settings" adapters?

Any ideas?