Is there a way to redirect read/write from DF0: to RAD: (for eg), so that utilities like (W)Warp can use RAD:
?

Yes.

You have to redirect output in NSD config file in DEVS: from df0 to rad, my single disk Amiga simulated df1 this way for multiple uses. The file contains directions

thanks.
um, it sounds like 'newer' thing, is there a chance that would work with KS1.3, as Warp seems to require it?

I haven't use KS1.3 since the 1980's when 2.04 came out; you might try a simple reassignment, but I'm pretty sure that DF0 is in the firmware for 1.3.

Could you define "Warp" as the Warp3D drivers, or the Warp Engine, or the speed the NCC-1701 when it goes faster than light?

its a disk packer, very much like DMS. seems the same company made it.
Unwarp works ok in KS2+, but Warp freezes.
I could use df0: in KS1.3 after all, but would need some utility to stop disk validator (and viruses that use it).

Is there any reason why you would need to use Warp? It only reads from trackdisk.device, you could use any ADF creator to replace it.

UnWarp runs on Kick 3.1, so there is no risk to start a disk-validator virus when writing to DF0. BTW, I just tried Warp on 3.1 and it worked without problems.

Disk-Validator is not limited to DF0. It will run from/for RAD, too.

Thanks Thomas.
Warp does seem to work on KS3.1 but at the end of compression it freezes. If not, could you please tell me filesize/version of Warp you're using?

I have a lots of duplicates in my 'collection':.adz/.dms/.wrp/.dsq.  The idea is to convert all (or most) of them to .adf, rename and then use 7z solid packing with large dictionary size. But, I'd like to do it so the process is reversible, to be able one day to reconstruct original files. It's hard because of different buggy versions, file_id.diz, algorithms, and so on. Some data needs to be saved separately (headers/footers). So far, I've managed dms and dsq (well mostly).  Its probably a bit pointless task, but at least I'm learning perl and bash.

Thomas, you're right, Warp works in KS3.1.
I forgot to enable sound in winuae, and it makes a beep after compressing.
BTW, your tsgui works better than dcp in KS1.3.