In order to change the width of the label the only thing you need to do is to add the following css rule to the page syles.
Please also find attached a sample project that is demonstrating the approach.
For the second question, we are not aware of such an issue. CDN is just an optional feature used to deliver resources from a third-party server and cache them for better performance. Please verify if you have referenced correctly the Telerik.Web.UI.Sins.dll file and also it has to be the same version as the Telerik.Web.UI.dll. If you still encounter a problem with this please open a support ticked and send a demo project that is replicating the issue.
I am looking forward to your reply.
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