Save and Build Custom Theme Failed

Hi,

I'm trying to save and build a custom theme, I get the approved message, where it says that the theme has been saved and built,

but there is an error message as well, with the error: "Uncaught TypeError: Cannot read property 'replace' of null" .

When i assign the Theme to an application, the application opens without a theme,

and I can't even see the saved application in the Theme Designer.

EDIT: I just saw the errors in the console log, they are saying that the sap/me/themes/sap_blucrystal/library.css could not be found.

I appreciate any help.

Regards,

Georgi