In the future, it would be nice if you would post a new topic instead of bumping a 1.5-year old thread that has little to do with your question.
But to answer your question, there was a DSL 1.1. It fixed some glitches that were uncovered and rebalanced the motors and some weapons like the DSL bars. Even the biggest motors were little more powerful than an HP Z-tek, though, so V 1.2 was promptly developed.
I don't think 1.1 is necessary to install since it doesn't appear to be in the download database.