Using a "repack" is a form of software piracy, as it constitutes using copyrighted software without a license. This is strictly prohibited by the software's End User License Agreement (EULA). The legal consequences can include significant fines and legal action from the copyright holder.
Since Syntec IDE can often be executed directly after decompressing without a formal "install" process, a repack may simply be a compressed directory tailored for specific controller versions.