[Programs installed: DOPUS 12.9 and WinRAR 5.60]
I created several solid rar5 archives via dopus options but the output is always a regular, non-solid rar4 archive. This is seen in WinRAR's Show Information tool. I also just installed 12.9.2 beta and got the same results.
Thanks for noticing this and letting us know!
I think this was due to a slight change in behavior in a recent WinRAR update.
A fix has been written and will be in the next update.
(For creating solid RAR 5 archives, there isn't an explicit option in Opus but you can -- once the new version is out -- do it by making it the default in WinRAR itself via Options > Settings > Compression > Create Default..., and then selecting the RAR 5 option within Opus.)