TKROM board reproduction

I have put sockets in a TKROM board (Shadowgate). Now, when I put Shadowgate on the Eproms everything works fine. So, the soldering should be ok. However, if I put either Kirby or Mario Adventure on the Eproms, I get a very glitchy graphic. The game plays but only very glitchy. Does anybody have an idea how that can be?

Could you please post some pictures?
For what you've said, it seems like a problem with the CHR's A17 line.

Many thanks. You guessed almost correct. It was A16 that had a loose connection.
Thanks for your help!