In general, reports are data-driven which allows you to change an item's settings via conditional formatting
used as Value property, all based on the data fields.
So, my recommendation is to create TextBox items design-time, then modify their properties on ItemDataBinding event and use conditional formatting or binding rule to conditionally hide them. In case you have a complex requirement to show/hide data, you could create an user function
that allow you to extend the default behavior of the Telerik Reporting engine.
As a side note, more considerations on this topic are provided in Modifying or Creating a report at Run-Time
Back to your question regarding the incorrect behavior of events, we would need to check the code of event handlers in order to provide you further suggestion. You can share it here or in a new support ticket
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