Hello Baker,
yes, I also thought about why not use a small function with a centerprint loop and a nextthink value to cover the 10 sec.
But I thought that centerprints bring automagically that "notify" sound with them. Just like the one from the start map skill settings message.
It always "beeps"

But then I looked into the maps ent file and discovered that the sound is not engine sided hardcoded to centerprints.
There are even 3 possible sounds available.
Default is without sounds, so this "workaround" should be an easy way for doing it.
Thank you for your suggestion Baker.
It has something to do with the "small mod compilation". A SSQC sided version of a map introduction text.
But the more I think about it, the more I think that this would annoy people.
Maybe I should switch to bprint instead (which is only visible in console for the interested user).
But who knows for which other purpose this thing will end...
Anyhow, it helped me to learn a bit more about QC. And that was defenitely worth the trouble.
Thank you again Spike and Baker for sharing your knowledge to the ones in need.
Best wishes,
Seven