Thank you, it seems to have been solved!
Yes, I'm using 1.5.1. I'm just waiting for the new 1.5.2 to show on the admin panel or on softaculous to update it (I thought it might solve the issue)
I have no idea why it started out of the blue like that. When I was on filezilla uploading the run.php you referred me to, in the very last second I noticed that the sizes of the files didn't match. The one that was on the server was a little bigger (3.7xx instead of 3.506). I wish I had saved it and sent it to you guys so you could investigate it. But when I noticed the discrepancy it was too late, I had already started the transfer/replacement. Oh, darn!
no more error messages so far. Let's hope it'll keep this way!... :)
