Hello Webcastor,
As I was clearing up conflicts in the database, I finally found the root of the problem. I did a search for %jck% in the whole Mysql database and I found (amongst many others):
2 matches inside the table #__cck_core_fields :
There in Article Introtext and in Article Fulltext the column OPIONS2 was set to: {"editor":"Jckeditor","width":"100%","height":"280","import":"1"}
I changed "Jckeditor" to "jce" and plop ... now I can open a new article with Seblod without getting a blank screen!
So if this helps anyone, don't look further than that place in Mysql in a first instance!
Message to 'Seblod core developers': It seems that when we eliminate the JoomlaCK editor to replace it by for example JCE and make the changes in the global settings of Joomla, Seblod does not follow the new settings in the core. Eventhough the whole site switches to JCE (including content types) - new Seblod-articles don't. Hence a blank screen ...
Kind regards,
Bernard