The problem occurs when trying to use anything from the 0x7f to 0x80 range, or the \uf0XX range. My workaround for EscientPronto was to assign the play/pause symbol directly to the firmkey in the editor and then use a single space ' ' to wipe it out if not needed. I know this won't be acceptable to many of you so here goes...

I've contacted Philips about this problem and have actually been sent a revision of firmware (alpha only) to test and can confirm that this has been fixed in what should be the next firware release.

No ETA on actual time yet but rest assured that it will be addressed.