Problem really was with the effect thing. In other PC, I added the Noise Effect to layout0, and then copied that layout to serve as a basis for the other ones. Problem is, in this PC, the effects are not listed there. I had to copy+paste the layout's content to other freshly made layout and the problem was gone.
Still, quite a nasty bug for it to be detecting and effect but not listing it.
If you really think you have a reproducible bug, then please post it in the Bugs section, ensuring to follow the Bug Report Requirements.
That way, Ashley can investigate and hopefully fix it for the benefit of all users.