Leaving UK on FP, but returning on EEA2 residence?

[obormot]

We just got the EEA2 residence permit for my mother from the post. It took exactly 6 months (documents were sent on July 17, 2013). We requested passports back in August, so the permit arrived on a separate paper.
Now, my mother left UK about a month ago, and she is now abroad. I plan to send her EEA2 by some secure way.
Did anybody have similar experience?
Will she have any trouble returning (given that EEA 2 arrived when she was abroad)? How important is it for me to pick her up abroad to come through immigration with her? Or will she be OK on her own wit me waiting outside and my cell number with her on a piece of paper? She is 68 and does not speak English..

[Jambo]

Not an issue. She can travel alone.