This issue mainly happens on a 64-bit machine. When you accept the EULA displayed by MBV, it writes the acceptance setting in the 64 bit registry hive.
But BizTalk360 is 32-bit due to restrictions imposed by dependency objects like ExplorerOM, hence it always look at the 32-bit hive (WoW64 in a 64 bit machine). To fix this issue, please create following entry in the registry.
You can either create the above Key's manually by opening regedit.exe ("Run as Administrator") or download the attached .reg file and then double click to import.