Answer:
Information on the calculation time can be found in the "sm_.LOG" file. This file is saved in the "!solver" folder in the working directory of a model.
To go there, open the subfolder of the current program instance and the opened model in the working directory of RFEM 6 (Image 01).
The file can be opened using a text editor, for example. The calculation time is listed at the end of this file (Figure 02).