Solution
Yes, this is by design. The "Embedded UI" feature is only supported in English and cannot be used with the Japanese locale. To enable the "Embedded UI," you need to change the locale setting back to English. This requires using the English version of the Real-Time module on both the host computer and the RT target. Note that if you use 32 bit version of LabVIEW, the English and Japanese versions of LabVIEW (32 bit) cannot coexist, so you will need to uninstall the Japanese version and install the English version.