I received an error after I have tried to import the theme into "UI Theme Designer"

Ireceivedan errorafter Ihave tried toimport thethemeinto"UI ThemeDesigner"

Isthere anyone who knowswhat I shoulddo toget rid ofthis errorandcan use theUI ThemeDesigneagain. In that case,I wouldbe grateful foranswers

Errorswilllook likefollowingwhen Ishoulduse UIThemeDesigneand I can notproceed