TemplateEngineException in ITemplateResolver chain with nested Spring form binding

A Spring MVC view rendered through Thymeleaf's TemplateEngine process path can fail with a TemplateEngineException when the configured ITemplateResolver chain resolves a template that binds a form-backing bean using th:field on nested properties or collection indexes. The exception may surface during parsing or rendering, depending on whether the failure originates in the resolver's template mode and dialect selection or in the expression evaluation for th:errors and th:errorclass.

The unresolved behavior is whether field names, BindingResult paths, and SpringEL expressions remain aligned when the backing bean contains nested objects or collections. A mismatch between the property path used in th:field and the path expected by Spring's BindingResult can cause the template engine to raise an exception rather than render validation messages, but the boundary between resolver configuration errors and expression evaluation failures is not always clear from the stack trace.

This behavior is version-sensitive across Thymeleaf 3.x lines and Spring Boot auto-configuration, so the exact exception type and message may vary. Which component in the ITemplateResolver chain surfaces this error, how do nested paths interact with BindingResult during the process call, and what verification confirms alignment without altering resolver settings?