I found a new version foobar mobile for MS WP8.1(Lumia & HTC M8 wp) and updated it in App Shop.

However,it failed loading “Now Playing” interface and a simple "Loading Skin" prompt is displayed. It's so difficult to control without Now Playing page.
Also, custom skin is not able to add and load. I've tried to uninstall it, dowload and reinstall, but this didn't work.

How to solve this error? there's no such issue in the old version but I can't go back to the old one because of WP limitation. What a pity!!