Well, tried this at home; no problems at all!
It looks like the problem is caused by pc at my office 🙂
I think the more strict security settings or the fact that Internet Explorer is the mandatory browser there is causing the problems.
Sorry for using up your time!
Tried Custom Sidebars for real now: Great plugin!!! Thanks for your effort!
Ok thanks for your fast reply and help offer!
I will have to check this out this evening, so please be patient with me.
Thanks,
Bert