Dear Moritz, I propose that you insert the change in line 645 of transient_ctmrm.c, as you seem to know best currently how model checking CTMRMs should de done. The code looked just wrong to me but I was not completely sure, that's why I didn't change it immediately but inserted a comment. I think that nobody feels really responsible for that code at this moment. I have no idea why uniformisation seems not to work. I recently published a technical report pointing to some errors in Fox--Glynn () and created a branch of MRMC in the official repository with the corrections, in the hope that they will make it into the next version of MRMC. I propose you do something similar and refer to "your" branch of the MRMC source tree for the MSCS article. Kind regards, David.