I'll give it another chance, by clipping almost everything off and planting it at a good spot in the garden.
Maybe it will feel better than in a (big) pot, thrive and flower with that bright-red color.
...If not, this gift from a friend, who got a wrong delivery, will be banished after all!

The website link mentioned on the first page has expired and is no longer available.

Available from - Hof Jeebel Biogartenversand
http://biogartenversand.de/index.php?cPath=158_239 info@biogartenversand.de

I became this rose this year in spring from a friend, that got it as a wrong delivery from a nursery.
I wouldn't have chosen it, but wanted to give it a chance.
It came with lots of purplish-blue irregular spots on the (cut) canes of the bare-root plant.
New canes emerged during the season and all the spotted canes died/did not grow.
Now in Fall, the new canes are affected too with those purplish-blue irregular spots. Similar to canes that are infected by Pseudoperonospora sparsa, or downy mildew. (I strongly believe it is downy mildew)
It will be thrown away.