Underground Mission seems to be unfinished - in level 10 there's an item stuck in the wall meaning you can't complete the level. If you cheat and collect it anyway, there are 6 (I think) more levels after it, all mostly functional but exhibiting varying degrees of brokenness. Strangely enough it does have a fully working ending screen though:
oh yeah, and the Chinese on the level intro screen reads 地道战, Di Dao Zhan. Presumably this was (or would have been) the Chinese name of the game - Waixing released something with the same name but it's completely different.
and on the subject of Inventor games, Power Boat has no apparent ending, it just loops back to stage 1.