Rhienne, I think all the info is in the book; this is not really anything new.  But the quote is from Robert Jordan himself, so it adds a bit of authenticity to have it directly from him.

Daedelus, "algai'd'siswai" means "The Fighters of the Spear."  What you're probably thinking of is "siswai'aman" which means "Spears of the Dragon" and implied ownership.

I'm confused, did they say that Jain Farstrider turned to the SHadow because Graendal compelled him? How early was she freed? Or was that just a subtle hint as to who sent Jain to Ebou Dar?

I think it was about sending Jain to Ebou Dar.  I found a quote from Team Jordan that says:

 

Ishara

There has been some discussion lately on the identity of the old man seen in Graendal's palace. Many of us believe that it was Jain Farstrider, the same man who wandered into the stedding all those years ago. But some have recently begun to think it could be Alsalam, as the descriptors are similar: older man, long hair etc. Can you confirm that the old man from the stedding and Graendal's palace are the same person: Jain Farstrider?

Alan Romanczuk and Maria Simons

(They whispered to each other for a bit before they answered, we offered to put our fingers in our ears and hum...) It can't hurt to tell you all—yes. It was Jain Farstrider.