The timeout is unrelated to the controls, but the XamlParseException is mostly likely because you forgot to enable XAML Compilation (aka XamlC) or give custom controls an x:Name (see this section
in the Troubleshooting article).
This is a known limitation of Xamarin.Forms on iOS when the custom controls are in an external library, not just Telerik controls. The iOS linker will optimize out any code that isn't referenced.
The fix is simple give each control an x:Name (this is rather inconvenient), or enable XamlC
on the entire project so that all XAML-instantiated controls are included.
If you have any further trouble, please open a support ticket here
and attach your code so that we can investigate further.
Lance | Tech Support Engineer, Sr.
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