Ok, this is a decision which will work for you.
With Mp3tag you can work after you have split the big mix file into parts.
So far as I know something about Mp3tag, it is not possible for Mp3tag for doing such text manipulation you need to convert a given textual track list of "track artist - title playtime" or "track.artist - title - playtime" into a detailed .cue cuesheet list.
Mp3tag works on audio files and can create reports about data given by these files.
Mp3tag can also do simple integer math, calculate sum and such, but cannot work with fractions of seconds in a simple way.
The calculation about fractions of seconds needs rather sophisticated usage of the Mp3tag math functions and I am not convinced yet, whether it could be done or not.
Well, since the 'Frames' value is an integer value, it should be possible anyway.
You should try to get the original cuesheet coming along with the big mix file - or sit down 5 minutes and write the list manually into a text file using some text editor.
You can also search the internet for free tools or web services, which can, for example, convert a list of freedb entries into a cuesheet format.
DD.20110320.0836.CET
Edit.DD.20110321.0940.CET