This isn't Dynablocks from 2004. The screenshots clearly look like Roblox from 2006.
By the way, if you guys want the full client, just find the ROBLOX Client from March 26, 2007 on MaximumADHD's Github page! I can't link it here since I have no idea if itch.io will allow other sites.
Client_version for ROBLOX is: 0.3.368.0
Also, if you really want a "DynaBlocks.beta" (Roblox was never named that, by the way) experience, then just get G3D-Fun (aka Blocks3D, ZipBrix)
NOTE: Most of the time, Github doesn't have malicious files. Still be careful though!