Is is a modification by DShiznit that adds much more content to the original beta blockland (that was free.)
It's still being developed.
However, there was a rumor that it detects RtB files in the folder and purposely destroys it, the user's computer, and itself.
Which won't happen if you don't rip off scripts from it.
I had TBM and RTB installed and nothing ever happened, and I never saw a single thread on either blockland, TBM, or RTB's forums back when the original TBM devs were running it. Though, considering how dumb DShiznit is/was when I used to play TBM, he may have put something malicious in The Orange Block.