2021-10-08 Thanks to Jack Lance, Karoo for finding a severe bug in the error checking, as well as other improvement opportunities. 2023-07-09 Thanks to dohz for finding a transcription error in puzzle #3, now fixed. Also, numbers characters are now slightly enlarged. 2023-11-28 Numbers without circles will now cause an error if crossed by lines; and correct areas are highlighted. 2025-03-09puzzlettersPinkHoodie fashioned 1 Chainlink (classic) puzzle - kiitos!