Luca,
JLinked v2.0 had a lot of changes in it, including a way to create custom Login button images similar to how JFBConnect can do it. With that, you can use any image or text and just add call the JLinked Javascript to login. The SCLogin module expects that behavior to be present. Unfortunately, there's no mode in the new SCLogin module to fall back to the older JLinked v1.x methods. For more information on the changes, see the
JLinked Changelog
.
JLinked v2.1 is also expected later this month, which will add automatic account creation as an option so the user won't have to see any forms during registration. There's always new features planned, and we simply can't support all the older versions of our extensions with the newest features.
I'd recommend downgrading back to SCLogin v2.0 or upgrading to JLinked v2.0, whichever works best for you. I think SCLogin shouldn't have any issues with JFBConnect v4.2. However, that's a pretty old version as well. v4.3 was released last year and v5.0 came out earlier this year.
Thanks,
Alex