Hi,
It seems your Github post was closed because you did not provide further info or a project when requested. So what happened with this, did you manage to fix it anyway?
I have exactly the same problem with SfComboBox (v17.1.0.51). As soon as I insert on into my page, I get the same "exception occurred while rendering the control" error, even without me attempting to set any properties.
Without a fix or workaround this means I either have to forgo the advantages of being able to use the previewer, or I drop Syncfusion components.
Thanks
Paul
PS. I am using Visual Studio 2017 (v15.9.9)