Spinner property value bind trouble (C#,xslt)

I try bind a data to property "value" of spinner control but any no data type works. Try pass double like the "Ruler tool tutorial"

https://community.coreldraw.com/sdk/w/articles/218/creating-ruler-tool-for-coreldraw-or-corel-designer

try use wrapper double, marshal types.

Any light

entire xslt code

https://github.com/bonus630/FacaCaixaAutoToolBar/blob/master/FacaCaixaAutoToolBar/AppUI.xslt

entrie datasource code

https://github.com/bonus630/FacaCaixaAutoToolBar/blob/master/FacaCaixaAutoToolBar/DataSource/FacaDataSource.cs