No, this is not a bug.
Vast parts of the Replay Mod have been re-written for the 2.0.0 versions.
Some lower priority things such as the Replay Editor and the Asset Manager haven't made it into the 2.0.0-b4 versions as otherwise we'd still be writing and no 2.0.0 version would exist at all.
The Replay Editor (trimming only for now) has been re-written and will be back in *-b5 (to be released very soon).
No work on the Asset Manager has been done till now, there is no ETA. Last plan I am aware of expects it to return in 2.1.0