Just to close this out for the general knowledge of future forum-goers: my entire guage cluster was swapped out under warranty. It was displaying no tach reading, flashing temp bars, and accumulating kilometers as fast as it should be accumulating hundredths of Ks. The tech who rode it around to the back remarked about how cool it was to do 900kmh in the parking lot, and this affected both the odometer and speedometer which means they had to guess at my actual mileage and have the KTM factory program that number into a new guage cluster as the odometer setting.
Hopefully this doesn't happen to anyone else- especially not out of warranty! -but the service manager said he'd seen a lot of KTM clusters go haywire on their street bikes, so even though this was the first Adventure they'd had with it it was not unheard of. She works fine now, but I have to figure out how to get my temp sensor back into degrees F and not C...