Using widgets on pages should not cause any problems.
I understand your frustration themes and templates are basic functionality, but we are currently experiencing bugs with widgets placed on templates. They appear un-editable in the backend, but OK on the fronted.
Concerning the problems you have with navigation please refer to the comments here and note changing the StartingNodeOffset from 1 to 0. Please note that template is developed from a third party vendor.
Attached a file with the project manager 4.1.1405 you mention to have trouble with.
the Telerik team