In the press release it is said that the CoR finds the present proposal too complicated and demands a reduction of the minimum number of countries from 1/3 to 1/4.
It is a pity that the press release doesn't link the actual report - a clear communications failure
So we might have to wait until 12 July when she presents her opinion to the European Parliament Committee on Constitutional Affairs (APCO)...
Update: Thanks to @Dana_Council from the Council press service, I have found the draft opinion and the amendments tabled.
Will take a more in-depth look later on.