Thanks guys, double quotes did the trick. I think I've spent a full day trying to make it work.
Btw, I've read almost all of your TimeQuest manual Rysc, pretty awesome work.
Still, there is a few things I'm missing (mostly regarding some multicycle assignments, since I have a regular clock for Altera's TSE and 90 deg phase shifted for TX clock of the GMII i/f of the PHY - data is arriving way too late; everyone on the forum seem to have RGMII PHY and I can't get all the answers I need), so don't mind if I start a new thread regarding that :). I just want to make sure all the clock assignments are correct first.