I am not really into FILD, but to add to what BrandonBoss said, i don't think you are supposed to do movement physically during FILD, focusing on physical waking body is not the aim of WILD(and based techniques), so instead try visualizing movement mentally without thinking about physical body. I hope that helps.
As for what anchor is, anchor is what you are focused on mentally while WILDing to keep awareness, be it mantra, visualization, count, and so on, which anchor works best varies from person to person and it's always good to try different one if you have problem with current one.
Also check out this tutorial for some good information on lucid dreaming and WILD, which can help with WILD-based techniques too: http://www.dreamviews.com/wild/