I want to report minor bug, not sure is this right place to do it so excuse me please.
Note i don't believe this is exceptionally 4.x issue.
"screenUtils.toPt: input not recognized!"
This is caused when setting xoffset/yoffset of PictureMarkerSymbol to "-10px" or "-8pt". As i assume problem here is regexp fails to match '-' character of given expression.
Work around to this bug at this time is simply to use numeric (non string) in Pt offset values, anyway this should be fixed.