I have been using PrimeGrid for a little over a week now. I just downloaded proth.exe just to see if I could test some large proth numbers for primality (K being larger than 10000 of course so I don't overlap with this project :) ). Anyway, when I tested 12345 x 2^400001 +1 I got a memory error. This confused me because all of the 3,300 proth numbers I tried with PrimeGrid are at least that big and I had no issues.
The Proth.exe I downloaded was 7.1 which I think is a few years old. Any advice? Is there a newer, better version or is this a fluke?