No currently. However mid-kid is working on 9.0-9.2 mset, if you want it, go help him - if you would like to have it so much. Or else you 'd better choose wait.
See the cake hax for rxtools here:
https://github.com/roxas75/rxTools/pull/55
It is decrypting those FIRMs, and patching those. You know it needs patched ones to work. Unfortunately roxas pushed several releases onto the github, all names are similar.
If you really have the latest one with correct Firmware.bin, it should install successfully and bother you nomore.
If not, tell me what it displays, there should be a progress bar, such as [....x..] or [.......]. Make sure you are using the latest please.
And for the MSET downgrading.. It is to install an exploitable version of MSET, if you are already using DS Profile, there is no need for that (already exploitable).
BTW, I really like to have someone help rxTool team with the documents, at least its tutorial and FAQs, would be included in release zip file.
If you want to help, get a github account, and come to https://github.com/roxas75/rxTools/issues/56. No coding ability needed.