I've found another strange thing here, check out:
Roundedge in 1.18 : http://tours.viewit360.se/develop/bug_reports/roundedge/18
and in 17.5 : http://tours.viewit360.se/develop/bug_reports/roundedge/17.5
The xml code is identical. In 1.18, it seems that textfield has twice bigger "roundedge" value for some reason.