Persisting dynamic files in GWT (Plugin) Classic Development mode?

We've customized the compilation process for GWT so that when a GWT compilation occurs, some dynamic content is created underneath the war directory.  In Eclipse, this content is actually written to the filesystem in Classic Dev Mode so is permanently available afterwards in the project directory, but in IntelliJ, it seems it's sandboxed so that it doesn't actually get written to the filesystem and is only available via web access (e.g. browser "save as") while the server is running.  Is there any way to disable sandboxing, perhaps just for one subdirectory?

Our goal is that this dynamic content be available offline afterwards, and when GWT is toggled to SuperDevMode.

Note that in SuperDevMode, Eclipse sandboxes the project like IntelliJ because the SDM server is serving "fake" content.  So our approach in Eclipse is to have the user run in Classic Dev Mode to generate the persistent files, and then toggle to SDM and the files are still there.  However, this isn't working for IntelliJ, which will seemingly require an ugly extra step of manually copying the files from a browser to the filesystem.